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Red Hot Manifolds

Hello all,

Last year there was a very good thread on 454 engine overheating problems, with some very good responses and solutions to the problem.

Unfortunately, the thread got lost in cyberspace. The following message is posted for John S, who needs our help on this subject.
Thanks,
Les

The following is a very lenthly discussion, but there is much good information!

John comments:
I bought a 1993 37' Winnebago Vectra in August of 1999 with 37,000 miles on it. It is on a Chevy chassis with a 454 engine, and an automatic 3 speed transmission with overdrive. Before I bought it I took it for a test drive, and I could tell the exhaust manifold(s) were cracked. As a condition of the sale, the dealer replaced both exhaust manifolds. In the course of doing the work, the tech discovered that they must have been replaced at least once before because 2 of the bolts were cross threaded, and the dealer had to replace one of the cylinder heads along with the exhaust manifolds because of this.

I have since taken the RV on several trips, and have been very pleased with the performance on the road with one exception - the engine temperature gets VERY high. When cruising down a flat highway at 60-65 the engine temp (according to the gauge) stays right around 210. As soon as I encounter the slightest hill, the temp rises right up to the edge of red area on the gauge (240). On our last trip, we were heading West on the Mass. Turnpike. There is one section where there is a very long (about 10 miles) ,steady hill. By the time I was halfway up the hill, the temp gauge was well into the red area on the dial, and when I finally reached the top, the temp gauge was all the way into the red (260). No wonder the exhaust manifolds keep cracking! My speed up this hill was right around 40 mph, in second gear. The engine did not sound like it was having a hard time keeping this speed. I probably could have pushed it a little harder, gained some speed, and got it to shift into 3rd, but I was afraid to try with the temp so high.

I asked the service manager at the dealer what could be done about the high temps, and his reply was "do everything you can to increase the airflow through the radiator and over the engine", but he would not offer any specifics. Is there anything you can suggest that I can do to prevent the engine from getting so hot, without spending a fortune in the process?

There is a large fan on the engine side of the radiator, that must be on a clutch or something. When I first start the engine, put it in drive, and take off, I can hear the roar of the fan, but it sounds like it stops. I cannot tell if the fan turns on when I am driving down the road. There is also a small electric fan in front of the ac radiator that must be on a thermostat. Whenever the engine temp hits 210 (whether or not the ac is on) I can hear the electric fan turn on. It brings the temp down a bit, then turns off until the temp gauge hits 210, then turns on again, etc.

Sorry for the long email. Any insight or suggestions would be appreciated.
I am afraid my engine and transmission will not last very long at this rate.
John S.

John, you are right on the mark with why the exhaust manifolds were cracked. This is caused by extended running at wide open throttle (wot). Can your mechanic recommmend a lower temp rated thermostat (without putting the computer into cold-loop)? Other than fans on the radiator I would route some 3" flexible tubing (like dryer vent hose) from a spot near the bumper (put it out of the way of water and with mesh to stop debris) and pipe that sucker into the engine compartment. Good Luck and I hope others have some good suggestions perhaps from experiences similar to yours!
Kevin

Hello,
Had the same problem with my Suburban when I bought it. Scared me to death when I looked at the temp gauge and saw 240. From what I've been able to gather this has been a problem with the 454 for years. In trying to increase the fuel efficiency of their engines GM installed 195-210 deg. thermostats in all their engines starting back in the 70's. They also changed coolant passages in the heads to keep combustion temps high. If your engine actually hit 260 you may have cracked the heads around the exhaust seats(also a common chevy problem). The first thing I would try is changing the thermostat to a 180 or 160 deg. version and checking to make sure your radiator is not clogged up. You probably have a 4-5 core radiator already. I also changed the clutch fan out to a full flow stainless flex fan on mine and it made made a BIG difference in how quickly the temp gauge started it's race past 200. Use the biggest Flex-a-lite (brand) that will safely fit inside the cooling shroud. Some will insist that a flex fan won't cool as well as a clutch fan but I'll debate that issue all day. In Texas where it regularly hits 100 deg all summer, I've never owned a vehicle that didn't cool better with a flex fan than with the clutch. Besides, you won't have to wonder if the fan is turning at the correct rpm. If it's still hooked to the engine then it's fine!
A trans cooler will probably help as well. My 454 was tired after 120k miles, so I built a replacement last year. I used the Complete Edelbrock Power Package including the Performer aluminum heads, manifold, cam, timing chain, 800 cfm Q-jet, etc. I changed the rear axle to a 3.73 and put a shift improver kit in the tranny. I now have a 468 that will pull my 32, Airstream through the Texas heat with the ac on and not rise above 205 deg.
Good luck,
Kevin

A lower temperature thermostat can only delay temorarily an overheating problem. On a long pull there is so much heat being generated that even a 30 lower degree thermostat can only delay the inevitable for a very short period of time. The the cooling system has less capacity than the engine needs, it's going to overheat. And I've found there's always a longer or steeper hill - or a hotter day - out there just waiting <grin>. The trick is keep the engine at a uniform and reasonable temperature. 210 degrees is quite safe if you can keep it there.

First, you want to make sure the radiator and the cooling system is in good condition. The earlier suggestion to run an auxillary cooler is good because it takes some of the load off the radiatior (as well as helping keep the transmission form overheating as well). Another suggestion is to check the area between the radiator and the A/C condensor for debris. On two occassions I've found as much as 20% of the radiator blocked by stuff - mostly grass - that made it through the condensor only to pile up against the radiator. You can't see this from in front and unfortunately you mave have to remove the radiator to check it.

Also you may find it effective to block any alternate paths in front of the radiator where the airflow coming through the grill could bypass the radiator. The airflow will favor the path of least resistance and all those heat exchangers stacked on top of one another create a lot of flow resistance. You want to take advantage of that ram air, not lose it.

Finally, you migh consider having your radiator recored with more tubes. On a 4 tube radiator, adding another row increases the radiating surface by 25% (albeit with some increased resistance to air flow).

Finally, the older copy I have of the GM Motorhome Owners Manual has some specific suggestions regarding engine compartment cooling to help eliminate hot spots that can warp or crack exhaust manifolds.

Sorry about the long post - got carried away!
Tony H

Idea given to me by an old time mechanic, once a year change your radiator cap,do it when you are preparing yor rig for a long trip etc. or winterizing,at times your cap will be letting a small amount of pressure escape and it does not take to much pressure loss to cause overheating.
R.Pearce

John, I'm no engine expert but I've had a several Chevy 454 front engine motorhomes and I'm surprised no one a has commented on the fact that your thermo-clutch engine fan does not seem to be operating after initial start-up (when the fluid is cold). I've found that with a front mounted gasoline engine when the engine cooling fan cuts in you really KNOW it - my first encounter scared the dickens out of me, thought the engine was going to come up through the dog house. If the clutch is working I would think you should hear the roar before the water temp reaches 230 degrees. I have an auxillary temp gauge and when the fan cuts in the water temp goes down 10 to 15 degrees almost immediately (and so does the transmission temp gauge, but not as much). Anyway, that clutch is easily checked and could help your problem. Good luck!
George.

George,

I've had the same experience with the "thermo-clutch engine fan" as you. The first time I heard it come on when we were driving we had just gotten off of the freeway and had to stop at a traffic light. The fan kicked in and I thought for a split second that my 454 had turned into a jet!

Anyway, could you provide a brief description of the "easy" way to check the fan clutch for the rest of us who don't happen to know? It's that time of year here (over 100 degrees almost every day) and it would be nice to know that we have the cooling capability we're supposed to.

Thanks,
Mike
RVChem.net

Actually, from John's description it sounds like his fan clutch is working. It should make some sound on a cold start and then fade away in a minute or two (mine sounds like the engine engine rpm drops as it fades away). And the sound he's hearing when the temps get near 210 sound like the engine fan engaging ... the electric fan is almost completely silent by comparison. The sound my engine fan makes would be impossible to miss when it changes to full cooling.

As George says, when the fan cuts in, the temps come down noticeably and in a short time. On an RV trip two years ago with my 454, we hit some really hot weather climbing very high passes in southern Utah and Colorado. My fan started cycling at on 220 deg (and shutting down at an indicated 190 deg). As we got higher, the duty cycle was over 60% on to off. From everything I read, that's how it should work, but the on & off temps may vary from installation to installation.

While we're talking about cooling, an real no-no is adding bug screens. I've seen figures suggesting a reduction of air flow on the order of 20% and the GM Orange Handbook states flatly "Bug screens should be avoided if at all possible...(and if used) the screen should be removed immediately upon leaving the bug infested area". That publication also says if a screen has to be used, the screen size should be twice as large as standard household screening.

Not sure if there is any way to check the fan other than observing it in action. Maybe someone knows?

Tony Howard

Have to agree with Tony's posts.

There is a CLUE in your original post no-one has picked up on. You mentioned one of the heads was replaced. There is a possibility there is a leaky head gasket. If hot combustion gases are flowing into cooling passages you ARE going to have heating problems. There are several ways to check. With engine running and at temp. Remove rad cap and look for bubbles. Can also place rad. tester with pressure gauge on rad. and look for continous rise in pressure. Caution, these testers don't vent excess pressure so will have to keep a close eye on the gauge and vent excess pressure manually. The problem with these two methods is when leak is small and doesn't present itself except under engine load. The best method is: Some shops may be equipped with test instrument that replaces rad. cap and can detect presence of exhaust gases.

This engine overheating and cracking of Exh. manifold may not be related. What will cause cracking is thermal shock, having manifolds cool down too fast. When subjecting engine to high loads, make sure you gice the engine time to cool slowly. NO instant shut down of engine or immediate heading down mountian side whit foot off the gas.

Cracking is cause by thermal stresses (uneven temps) by rapid temp changes. Reducing rate of temp changes will likely prevent cracking.

There are other cause for creating stress in the manifold but will not take time to go into all the detail.
Mickey

I have a 92 southwind with a 454 with the electric fan and the whole 9 yards, and I have been having all of the same problems as all of you. It was to the point that on tall or long hills we would unhook the tow'd and the wife would drive it up and rehook on the level. Recently I took my unit to a rad shop where they checked out and then chucked out my aluminum rad, due to corrosion and mineral build up I only had at max about 20% cooling capacity. They put in a normal nonaluminum rad and since then I have had no problems at all other than I am considering putting in a higher thermostat because the engine seems to take all day to get up to running temp. The bad thing about aluminum is that the first time they overheat they start to swell and expand and the swelling can effect the passages constricting them making the rad get hotter and on and on and on. so I would suggest getting your rad checked out, it doesn't matter how good your fan is if the coolant flow isn't there.
Randy Z

Lots of great suggestions and comments on this subject.

I would add to the list by suggesting that the exhaust system be checked for any blockage or undersize plumbing. Also, check the fuel/air mix and timing of the engine. If one or both of these are out of specks heat can be the result.

On many engines, not just the 454's, the high heat in engine compartments has caused the vacuume hoses to deteriorate. This can lead to leaks and improper air/fuel mixture to only part of the engine. Hard to detect but can be a real problem when fighting and overheat situation.

Remounting the AC condensor coil and tranny cooler to a remote loacation(s) with electric fan(s) will reduce the cooling load on the engine radiator. Have done this on a couple of rigs with outstanding results.

Another trick I have used is to put a few small spray jets in front of the radiator and hooked them into the camper/motorhome water system. Turn on the valve when the heat starts up and watch it drop as if by magic. I use the sprayers designed for the low pressure water systems in gardens. Get them at your local Wallyworld or Home Depot type store.

Probably the best way to keep the heat down is simply to burn less fuel. That is just ease up on the throttle and watch the temperature gauge. I find it difficult to do this since my time is sooo.... valuable and I got places to see yet.
Mike Niemela

To help the cracking problem let your engine idle 3 to 5 min. before you shut it down. This will let it cool down slower and help on the stress from hot to cold.
cal

I can post this without Les's help this time, as I am using a friend's internet account. I can no longer access this forum through my own internet account (through work), but I won't go into that.
Thank you all for your great suggestions. Here are some thoughts after reading your responses. How can I tell for sure if that engine fan is operating like it's supposed to? I do definitely hear it when I start the engine cold (sounds almost like it would if the trans was in park and the accelerator was on the floor). After a few minutes, it dies down. I never really thought about it before until reading your posts, but I don't really notice it turning on with that same roar when I'm driving. The engine is not very noisy when going down the road. I definitely do hear the electric fan turning on at 210. It has that distinctive "electric fan" buzz. It is not very loud, but if you are listening for it, you can hear it.
Also, I noticed that the grill opening is lower than the radiator. A lot of the air going through the grill probably passes right under the radiator and engine. I am going to try to fashion some kind of shroud to direct the air through the radiator instead of under it.
I also plan to check the other things that have been suggested, but I'm going to start with that engine fan. A couple of people have said that it scared the pants off them the first time they heard it kick in when they were driving. If it should be as loud as it is when I first start up the engine, I have never heard that kind of roar when the engine gets hot. I was talking to my brother-in-law recently about this overheating problem, and he also mentioned that on his MH, you really know it when that fan kicks in. Either mine is some kind of different fan or it's not working right, because I can't tell if it's turning on.
Again, thank you all for the great suggestions. I will let you know the resolution, but it might take me a while....working is a terrible way to make a living!
John Sajdak

Assuming (there's that bad word) that the overheating is not engine component related (heads, gaskets and such) there could be several causes. The previously mentioned dibries in the raditator coils, thermostat, fan instelf, even engine timing and or fuel mixture being too lean. If these are alright maybe an engine oil cooler might help. It would help cool the engine oil thus bring the engine temperature down.
I've not heard the venting idea on street vehicles but it isn't a bad idea. It is used as a common practice on race cars to get air into the engine comapartment and other areas requiring cooling. Also, if teh transmition cooler is not large enough the transmition fluid that passes through the raditator under the standard hookup could also add to the engine temp.
Larry

John
From your msg. I gather that the fan is locked up when you start the engine, then it starts to coast after the engine heats up?? If this is true replace the cluch! It's broke.
Cal

I would use the optional "Flex Fan" to replce your clutch fan..I don't trust them...When they come apart say goodbuy to you raditor... I like the old engines that were made out of Cast Iron & steel & also a solid fan... Bob

John,
If you want to see if the fan clutch is operating, get a section of newspaper and roll it up fairly tight. Have someone crank the engine while you observe the direction the fan turns when running. Start the engine (should already be hot) and lay the rolled up newspaper against the blades so that you are pressing against them when the fan is rotating AWAY from you. If you can slow down and/or stop the blades without too much force, the clutch is not locking up. You will need to go out and drive the vehicle to get the temp up as running stationary may not allow the clutch to get up to operating temp.
You can also try bypassing the temp sensor that controls the electric fan. Once an engine has heated to the point yours has, it's hard to bring the temp back down again. Too much heat has been liberated into the oil, block, etc. If keeping the electric fan running continuously seems to help, you can either leave the sensor bypassed or get one that trips in at 160 deg.
Does this vehicle use a computer or is it one of the exempted carb. models?
Kevin

Looks like Tony H was right. I tried your suggestion, Kevin, to see if the fan clutch is locking up. I drove the coach around and got the temp guage up into the red. Pulled into my driveway, removed doghouse, and tried to stop the fan with a rolled up newspaper. Couldn't even slow it down at all. I still don't understand why I don't hear it kicking in though. Next, I plan to have the radiator checked out at a rad shop, and check for debris in the cooling fins.
Kevin: I don't know that much about engines, but there is definitely no carburetor there.
OK, I have another question. Could this possibly be caused by a faulty water pump? Can a water pump gradually die, or become less efficient at pumping water over time, or is it more like now it works now it doesn't?
I have noticed that when I start the engine cold, I hear an intermittent "knocking" noise that is quite loud, appears to be emanating from the water pump (although it is kind of hard to tell), and stops when the engine starts to warm up.
The overheating seems to be getting worse on each successive trip. On a previous trip, I remember seeing the water temp guage acting erratic. It would go from a higher temp to a lower temp very quickly (too qiuckly, like from 230 or so down to 190 in a second) and then right back up again just as quickly. But on that trip, the engine didn't get hot and stay hot, it would run pretty normal, except for the occasional hot to cool to hot fluctuations.
On the last trip, the engine would heat up pretty quick, and ran hotter than normal for most of the trip without any of the rapid temp guage fluctuations.
I should also mention that the coach has a rear heater that works off the engine. When the engine heats up, it blows warm air out of the rear heater. It also has "motor-aid" for the coach hot water heater. It uses the engine heat to heat the hot water. I'm assuming that these two things use the hot engine coolant as their heat source. If they do, could this be a contributing factor in poor engine cooling if the coolant is not circulating properly through these things, or are they on a seperate "circuit".
John Sajdak

John,
Yes, water pumps can go "bad" gradually, and over time will lose their efficiency. In an automobile or pickup truck, you probably wouldn't notice any difference, but since your pump is circulating water not only around the cooling loop of the engine, but through the various heater and water heater, plus the enginem it's entirely possible that your pump is "pooped"!
Also, with the work your cooling system is expected to do, be sure that you have a clean system (Flush it and back flush it to clean the scale off the inside of the coolant passages for good heat transfer) and, be sure that you have a thermostat that is working as it should. (ie: replace it with a known good one.)
You might even find where the hot water from the pump takes off to the extra devices, and install valves to stop the flow and let the coolant circulate the engine only during hot weather.
There may be more than one situation that you are facing here, and eliminating the obvious problem areas may be the only way to cool things down.
There have been some very good suggestions given you by other contributors, now it's up to you to decide how extensive you want to get with your situation. And, unless you can do a lot of the work yourself, it may not be inexpensive.
My suggestion would be to isolate the extra devices from the engine and see how the temperatures react, then procede from there.
Remember though, my advice is free, and worth every penny of it! :-)
Richard.....

I have found that if you can tolerate the extra heat in the cab it is a good thing (in a pinch) to let engine coolant circulate through the heater core. The heater core is another method of heat transfer, in effect a smaller and additional radiator. When the engine temp rises during long pulls on the grades, put the heater on and you will see a difference on the guage...but again, its going to be hot. Just dont compensate by turning on the air cond unit! This is an old trick by us drag racers. You'll notice when at the track the guys coming back on the return road have their heaters going full blast and doors open to let the heat out. Heat kills horsepower.
RHankins

I almost forgot about shaving the impellors in the water pump to reduce drag and gain Horsepower. If you ran drag cars then I'm sure you remember that trick, and changing pulley diameters on the alternator/generator and water pump.
The bottom line for John is, he needs his cooling system to operate as it should, and all our old tricks can work, as you say, "in a pinch", but my suggestion would be to go back to the basics and make sure each component is clean and doing it's job as it should and as efficiently as it can. Trouble shoot by elimination...Do you agree?
Richard S

Richard, I agree. In over 45 years of fooling with cars, trucks and boats I've found if you don't eliminate the obvious (read basic) things first, you'll wish you had in the end! And more often than not, it's the basic where the problem lies. It's so easy to get fooled by apparent symptoms and your own pre-conceived ideas. It's almost as if you should always have a check list of basics to chase down first.

I think John is on the right path by making sure everything on the engine's cooling system is up to original specs. The next thing to check is the engine itself (timing, ignition system components, lean mixture, etc.) to make sure it's all working the way it should.

One clarification - Mr. Hankins is correct about not wanting too much heat, but heat doesn't kill horsepower - it creates it. Basically, the hotter the engine combustion is, the more horsepower is produced. What heat does is kill the engine if internal parts get so hot they begin to melt or fail mechanically. The heat that goes into the cooling system or out the exhaust is wasted horsepower.

Tony

I concur, Tony. An engine is a heat device, and the hotter you can have the engine run without destroying the mechanicals, the more horsepower is produced for a given volume of air/fuel mixture. But, to keep on the subject of John's engine, he needs to be able to run within a certain parameter, or temperature range. His situation is the engine is running too hot for his comfort level. Each item that is eliminated from the questionable list brings him closer to the problem area. Any part that does not allow proper heat transfer, ie: a water pump that moves water too fast to allow a "soak" time within the radiator, a thermostat that is operating incorrectly, water jackets in need of a good cleaning, fouled radiator fins, and bad air flow caused by obstructions before the radiator core (other heat transfer devises). Any or all of these can cause his situation, plus many more that are not mentioned.
I tow with a conversion van, and know first hand about the heat generated within the engine compartment. I had to install a five tube radiator core in order to get the engine temps down to an acceptable range. It wasn't cheap, but it did what I expected it to do.
I'd like to know what John's remedy actually turns out to be. It might be something very simple.
Richard S

As soon as I posted the comment about "heat kills horsepower" I knew it would be misunderstood. Of course heat produces power by combustion. I was loosely refering to the negative affect that engine compartment heat has on intake charge temperature. Anyway, I do agree he should be looking for the problem and updating worn/old components. I would not advise using the heater blast as a solution and was referring to a previous post about shutting off the flow to the core (when it's better to leave it hooked up). RV's are definately in the severe duty category and something to be carefully attended too. Hope this guy chases this temp prob down with all the advice he's getting...can be frustrating when you're talking vacation involvement and such!
RHankins

RHankins: Yes, your comment was misunderstood. Sorry about the tirade about it. I hope that John can take all the comments, create a punch list and track down his problem area. Severe duty is a good way to refer to most RV driving. Before I changed out the radiator to a heavier duty unit, my cooling was marginal at best. And, if I came upon an overpass, well, there went the temps! Sometimes it would recover, sometimes it didn't. I found the problem radiator by checking the thermostat for correct operation in a pan of hot water, changed all the hoses (which were due to be done) made sure that the water pump was in good condition (ie: clean and not leaking), soaked the water jackets of the block with a scale/rust cleaner to ensure good heat transfer, cleaned the fins and blew out the oil cooler coils, the AC condenser coils and the radiator coils. I then ordered a heavy duty five tube radiator because: #1. the old radiator had a lot of scale in it that I couldn't clean, #2. The cost of having the radiator recored was just a little less than a new radiator. So, a new radiator it was! That solved my cooling problem big time!
I knew that the engine was in good tune, having done a tune up on it a month before.
Anyway, tracking down a cooling problem can be intensive or simple. The trick is to check each component and do it in a systematic order, hence the checklist.
My appologies for being so long winded....

Richard S

Rich, I've even experienced the rising temps by following the "dead-air" behind semi rigs. Some of these complications can keep you on your toes!
RHankins

Hey no one mentioned exhaust system... get a free flowing exhaust... no back pressure and the heat will vacate the engine more rapidly.. dual exhausts is better... headers is even better. A good radiator,clutch fan, lower thermostat and it's licked. Good luck!
jack

John,
Let us know what solves the heat problem. Im betting on the thermostate unless I missed it you never had it checked and it may not be opening full.OOOOOOOOr the fan clutch, Im with the others that say when it locks up you know it. Every one Ive heard lock sounded like you droped the trany into 1st gear on a heard pull.
Cal

You bet I'll let you know what fixes this. If I had posted some suggestions in response to someone's question, I would be curious too, as to what fixed the problem.
Here's what I have been able to do so far (in fact I did this stuff before I posted the water pump question above) -- flush/backflush cooling system, removed radiator and cleaned debris out of radiator fins and AC cooling unit fins (very little there-mostly bugs), had radiator pressure tested (OK), re-installed radiator and filled system with new 50/50 antifreeze/water mixture. The radiator is already a 5 core, non-aluminum model. It looks to be in pretty good shape (maybe it was replaced by a previous owner?). None of this helped any, but at least I know my radiator is clean.
I have a new thermostat and fan clutch, but have not had time to install them yet. The water pump is not leaking, but there is that intermittent knock noise coming from that area when the engine is cold. I decided to replace the fan clutch because it was fairly cheap, easier to change than the water pump, and maybe the knocking noise is coming from that and not the water pump. Even though I could not stop the fan when the engine was hot, maybe the clutch is slipping (I don't even know if that's possible) and not turning as fast as it should. I'll keep you posted.
John Sajdak

John, it is not un-common for the impeller to wear down on a water pump or even be slipping on its shaft. Either problem would certainly cut down on your water circulation. Have you removed your radaitor cap, run your engine untill the thermostat opened up good and observed the circulation by looking in the radaitor? The circulation should be obvious.
Leon

Have you checked the possibilty of a blown head gasket? I'm sure there are several ways of duing this, but the one I use is to remove the radiator cap, let engine warm-up, then check for air bubbles appearing in a constant flow up the filler neck. This could be the problem. Good Luck!
HAPPY CAMPING!!!!!
Jack Hansen

SUCCESS!!!!
Anyone care to put in a last minute guess? OK, OK enough with the suspense.....it was the FAN CLUTCH!!! Seems that even though it was locking up when the engine was first started cold, it was not working after that. I have never driven a vehicle with one of those fan clutches in it, so I didn't know what it was supposed to sound like. With the new clutch, the fan kicks in whenever I speed up after slowing down, like stopping at a light or to make a turn. It also kicks in as soon as the temp guage goes above 210. Now I know, there is a very easy way to check the clutch for proper operation. When the engine is hot, shut it down and try to turn the fan by hand. It should not turn at all without also turning the fan belt. Also, it should not turn at all (by hand) when the engine is cold. The new clutch was locked when it was taken out of the box.
Thank you all for your good suggestions. I printed this thread out to save in case I ever have this type of problem again.
John Sajdak

  

 

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