Got a head scratcher. Customers 7G (92V) is running hot. I'm talking it'll get clear into the red just tracking down a road. We've replaced the thermostat, and water pump. We've removed the radiator and had it professionally cleaned. I've disassembled the heat exchangers and cleaned them. I've checked the fuel timing, I've ran the overhead. The radiator job seemed to help alot until the weather actually got hot. In my opinion the gauge is slightly off but a laser temp gun is showing 208ish on the head. Oil cooler is 225. Trans cooler is 190. Any ideas? Are these temps within spec? Nige? TCtractors?
What is the trans oil temp? You checked the fuel timing, has someone been working on it? Could it be timed up to #6 instead of #1? Later Bob
Can't add anything much to what Bob's already posted. 1st question is has any work been done on the engine recently..? Random thoughts Is there any sort of shrouding around the radiator that could be missing thus reducing airflow over the core..? You never mentioned fan or fan belt/tensioner condition. Could the fan be turning too slow..?
Don't know what sorta fan is on it but have seen a fan put on the wrong way round on a 25B that caused it to run hot, looked all right but just didn't cut the mustard in that it didn't move as much air as it would have had it ben on the right way, loose belts and worn pulleys would be another suspect.
Trans temp is between 185 and 190 where it comes into the heat exchanger. About 178-182ish where it comes out. I put new belts on it just to cover my bases. I inspected the pulleys and they're all good. Fan is facing the right way and turning good. I haven't put a tachometer on the fan but it's moving a ton of air. All shrouds are in place. No work has been done on the engine recently. It's got about 900 hrs on an overhaul and hasn't been touched since. I assume that if everything is working like it should it should run right around 185? I also replaced the dust sucker part of the pre cleaner because some of the tubes were melted and soot was plugging up the air filter. Really thought I had it whipped when I found that. The filter stays clean now but it didn't change the engine temp at all.
Might be worth a check of fan speed with a tach, just to rule it out. Regarding the dust extractor, have you checked to see if it's sucking properly..? I''ve seen melted tube before caused by corrosion in the venturi inside the exhaust pipe that generates the "suck". If that's the case you'll have hot exhaust gas blowing into the air cleaner (that's what melts the tubes and coats the air filters in soot) instead of sucking and this will drastically increase your engine combustion (and hence coolant) temps. Did the problem start suddenly or have the engine coolant temps been rising slowly over a period of time..? If they've been rising slowly maybe it could point to something from the overhaul. Coolant temp I would say should run about 180-195 depending on the Part Number of the thermostat. Any idea what the Part Number is..? I can look it up. What coolant is it using..?
Is the cooling system pressure holding in the right range?
I can look up the ticket and see what thermostat I put in it. The problem originated this spring when it warmed up. We thought it was running a little warm in late winter but wasn't overheating. Once we cleaned the radiator core it cured it until temps got into the 80's. But now it's overheating even at 60 degrees. I'll pull the muffler off and check out the venturi.
You might have found something there. Take the hose off of the aspirator, hold your hand over it as you rev the engine. You need to feel a draw like a vacume cleaner. The draw is created by the venture and tube in the stack. The tube end must be positioned in the tear drops correctly to draw, if not hot exh will go into the intake. Any paper obstructing the top screen will cause the intake to draw exh into the intake. Waste machines have a check valve in the tube to prevent this. Later Bob
Completely out of left field, but is the oil level correct? Also the temps of the hose going into the radiator, and the one coming back to the engine, and the air temp in front of the radiator, and behind the radiator might help.
It seems strange that the engine oil cooler is at 225 and the head is only 208 and Trans 190. What is getting the engine oil so hot? What is the oil pressure running at. Is the coolant flow being restricted at the cooler. Also temp drop across the rad would be good for know.
Have you looked at the water pump? Early 3306s had a plastic impeller bonded to a metal hub and they would fail at the bond. In my experience, most of them have been replaced by now, but there's always a chance there's a few still out in the field.
CM, according to the OP he's replaced the water pump.
Oh yeh. Missed that. Cheers.
You haven't perchance got a folded core radiator in this machine have you?
we have a D7G (65V) I think is the same config as the 92v it has the folded core radiator in it, it would run hot after about an hour of operation, even walking the machine in second gear would get it hot, we replaced all the cores with genuine cat cores and it has run cool as since, its hard to get it to run any hotter then about 85 degrees C that's in the middle of summer in western NSW Australia where it isn't unusual for the temperature to reach 45 degrees C on a hot day. I would be making sure you only have about 7 or 8 degrees C of temperature drop over your radiator, (from top to bottom) anything more than that could indicate a restriction in your cores - lack of flow in your cooling system, or maybe take a coolant sample and send it to you local dealer your engine could be pressurizing the cooling system, cheers Pat
Off base.....but has it had a new muffler fitted??
Especially an aftermarket one that maybe does not have the correct venturi (or maybe no venturi at all) for the dust extractor system..?
The folded cores work good when new and kept very clean but once they got dirty they are about impossible to clean short of completely disassembling the radiator and then it was a chore to clean the outside 100% and if there was any build up on the inside of tubes inside forget it! Another of those designs that probably looked good on paper in a nice clean office. Designers need to spend a few years out in the "real world" before they are allowed to design anything!
It's got a standard radiator in it. Not the folded core type. The water temp is dropping about 20 degrees from when it goes in the top of the radiator then back out the bottom. I'm not sure what spec is but 20 degrees seems like plenty. Mobiltech I wondered the same thing about the engine oil and why it's getting so hot. Oil level is correct. The oil cooler is clean as a pin on both coolant, and oil sides of it. I'm going to look into muffler situation more. I went back to look at it yesterday but when I got there they had another machine down that was higher priority than the 7. It does not have the check valve in the dust ejector tube and the precleaner I replaced was definitely melted. Which after input from you guys leads me to believe that the muffler is rotted internally. The air filter isn't coated in soot like it was but that doesn't mean hot exhaust isn't getting in. Thanks for the ideas guys. I appreciate the pointers. I'll report back.
20 degrees temperature change from inlet to outlet in your radiator is pretty much the maximum you should expect. Easy way to check the functioning of the venturi in the muffler. Take off the flexible hose at the muffler end and put the tractor into 3rd speed TC stall. Do you have suction or pressure at the muffler connection for the dust extractor..? Also ask the customer if they replaced the muffler when they overhauled the machine recently.
Copy that. Thanks Nige.
Got back out to the 7 today. I took the pipe off at the bottom of the muffler and checked it out. When the engine is NOT under a load I definitely have exhaust coming out of the venturi port on the muffler. In a 3rd gear wide open stall it really is neutral. I held a paper towel up to the port and it neither sucked it in or pushed it away. But at any rate, under certain conditions it def has exhaust entering the intake and I never could get suction. So I'm going to get a Cat muffler for it and install it.
When working right the hose will draw like a vacume cleaner to blow the large pieces of dirt up and out the stack. To achieve this the end of the pipe inside the venture must be positioned where the exh flow is at maximum velocity. Later Bob
Like Bob says it should literally suck the chrome off a bumper hitch if it's working right. Have they changed the muffler lately..? Either way if you can get the muffler off you ought to be able to check the condition of the venturi by shining a light through in the same direction as the exhaust gas flows through it. You'll likely find it badly corroded or even disappeared altogether.
If new parts have been installed, my guess is the tube end and the venture's max effect are not lined up. Perhaps the stack has the teardrops and is not down tight enough, causing the tube end to be ahead of the venture in a high exh pressure area, Causing the feed back. Later Bob
I am hesitant to add this with the wealth of knowledge and experience that have already contributed, but the 92V that I ran had a reversible fan. I know you said that you checked the fan, but it might pay to make sure all the blades are pointed the same way, pushing air out through the front this time of year. I'm probably way off base, but it won't cost much to check!
That's happened many times. Later Bob
I did check the fan and fins, multiple times. Lol. But they're all facing the correct way and at half throttle you can't keep your hat on if you get within 10 ft of the grill. This thing is moving A LOT of air. I'll have a new muffler tomorrow and intend on installing it Wednesday and I'll check to make sure the stack and any other components are positioned/working correctly. Thanks again guys. Lots of good ideas.
Maybe try a straight through pipe to see if it works cooler. Years ago I was on an old 9G pushing scrapers.A week into the job and the coal board made us put a muffler on it.The genuine cat muffler was causing me problems in the water temp department. The fitter took it off at brew time and it ran sound. Windows were soon black though! Some time later I had the same demand on one of my D8H's. Took the straight stack off and fitted a muffler with no ill side effects. Just fitted a new Cat Classic muffler to one of my 8k's last week.Is working a few hours a day sound but will be on 12 hour shifts from Wednesday. Will report back if any problems as it worked cool before
Can't see the new exhaust giving any grief on this tractor
Nice old tractor nicky. Anymore pics?
Here you go.yesterday
O2D did you get your overheating problem fixed?
Sorry guys. Was out of town for a couple days. Short answer is no, I did not get the problem fixed. I removed the muffler and didn't see anything wrong with the standpipe, but the other internal parts were well on their way to rotting off and I figured it would only take a couple pinholes to ruin the venturi effect. So I went ahead and put a new Cat muffler on it. Did a 3rd gear wide open stall and it has tons of suction. Way more than it did with the old muffler. However, it didn't help the overheating issue at all. The engine oil is a solid 20 to 30 degrees hotter than the coolant. What could be causing that? The engine oil cooler is clean as can be on both sides. Starting to run out of ideas here.
So you're saying when you shoot the temp gun on the coolant inlet and outlet sides of the EOC, you're getting 20-30 deg temp rise? That's a lot! What's the temperature of the sump? Consider that an overheating torque converter will still take a while to overwhelm the cooling system and it is putting way more oil through its cooler than the engine is. Most of the heat in the engine oil comes from the piston cooling jets, but the only time I've ever heard of problems in this area is when wrong jets/pistons have been fitted. If you're convinced that the engine oil is bringing the coolant temp up, the only thing I can suggest is that the engine oil level may be too low or high. Have you got the correct dipstick and/or tube fitted?
Or the skidpan is full of mud???? When the rad was reinstalled did all of the baffels go back in correctly? Later Bob
I'm saying if I shoot the temp of the head where coolant is present and say it reads 205 (just an example) the oil cooler will read 225 or 230. And oil is what runs against the outer case of the engine oil cooler so I know it's the oil getting hot. At this point it's the only thing hotter than the coolant. Even when the coolant temp needle is well into the red the torque cooler and lines run about 180. I assume the dipstick is correct. It's the one that's always been in it. Keep in mind this problem didn't occur after major work. Yes, the engine has relatively few hours on an overhaul, but this problem showed up on its own.
I've just copied this from SIS; When the engine is at operating temperature and the engine is using SAE 10W30 or SAE 15W40 oil, the maximum oil temperature should be 110 °C (230 °F). This is the temperature of the oil after passing through the oil cooler. So it seems like you're on spec. Do you have access to another 3306 to compare temperatures? I've just got a gut feeling that you've got a flow issue. Have you checked water pump pressure? You should be looking for about 15psi.
The best spot for measuring the oil temp on the 3306 also checking the thermostat action is at the spin on oil filter, aim your heat gum on the side of the filter checking the temp at the top and bottom on the side of the case, you should see the temp build up then drop in cycles as the stat open and shuts. tctractors
like Cmark I think you have a flow problem to, you stated earlier in the piece that you have about 20 degrees C of temperature drop over your radiator (from top to bottom tank) in my opinion ( feel free to disagree ) this is about twice what it should be, I think you shouldn't have anymore than about 8-10 degrees C drop over your radiator, any more than that indicates a flow problem, I know Nige has said that 20 degrees C is about the maximum you should expect I think 20 is about twice to much, if your flow is down by 50% you get half the amount of coolant going through your radiator but the same amount of air, therefor it cools the coolant that is flowing through the radiator a lot more but isn't cooling enough of it. Put it this way, if you didn't have a flow problem in your cooling system, and your radiator is cooling 20 degrees C from top to bottom, and your tranny isn't running hot, you wouldnt have an overheating problem!
Pat, the OP is working in Degrees F, so as I said somewhere on the previous page a 20DegF (11DegC) difference from radiator inlet to outlet is about the maximum he should expect from a radiator in good condition. Truth be told it's maybe a little bit over; the numbers I have in my Rules of Thumb are 18DegF (10DegC) maximum for a conventional core radiator in good order. I agree with you that the fact the radiator is giving max cooling, or even a tad more than max, could possibly point to the coolant flow not being what it should be, but as the OP said early in the piece he's replaced the water pump. Blocked tube somewhere..? Shop towel lodged in a hole maybe..? But again going back to what the OP posted the engine was overhauled and the tractor worked fine for a while, this problem developed later. Maybe we got sidetracked on the issue of the dust ejector, but based on what the OP posted it was definitely dodgy and needed fixing otherwise the plastic tubes in the new precleaner he installed would have ended up melted just like the ones that were in there before. Like CMark I'm not convinced the oil temperature is excessively high.
And if the air flow through the radiator is restricted, as well as the coolant flow being restricted, then the temp drop across the radiator can look fine while it's not cooling enough. Hot air recirculating through the radiator would do the same thing. Four temperatures are needed, air in and out, coolant in and out.
Out here doing more recon today and may have found something. I've attached some pics of my temp gun. When standing in front of the radiator it's obvious that the top 8" or so is warmed up. About 140 to be exact. When you move your hand towards the bottom it's basically ambient temperature. I've got 80-90 coolant feeding into the bottom of the water pump. As soon as it gets to the pump it jumps to 160. That's what I would consider a big jump in 2 inches of water manifold. Lower hose. Water pump housing. Upper hose.
The thermostat seems to be operating perfectly but it's almost like the pump is just cycling coolant in the engine alot more than the radiator.
The coolant is going through the bypass and will until the regulator opens to the rad and closes the bypass. Later Bob
I'd be pulling that thermostat and hanging it in a pot of water on a stove, or a mobile coffee can and torch setup
All of that is perfectly normal if it's not overheated. Was that with the engine HOT, or normal? Yeah, it's a stupid question, but I'm not there and you didn't say, so...
Normal I guess. It'd been running for an hour or so but I'd let it cool back down. It cools back down within a couple minutes if you just stop and let it idle.
Take the temps again while it has the fever.
Could the impeller have come loose on the shaft of the water pump. I've not seen the water pump on a 3306, but I had a similar problem with a new OEM water pump on a cummins engine.
And double check the radiator. You've got a lot of expert advice here, but the simple advice is check the radiator. "Professional" or not it's still a reasonably safe bet to say it's NOT clean. Have you checked with a light on the other side and looked through it to see that there's no build up in there?
I've quadruple checked the radiator. The damn thing is CLEAN. You can see daylight through every fin, there's no dirt/grease/grime buildup anywhere on it and I looked through the cores when it was out and disassembled. I'm headed back out tomorrow to disassemble the water pump, test the thermostat, and replace anything if necessary.
When you have the thermostat/temp regulator out, check the lipseal that the sleeve runs on. Later Bob
I had the same problem with a D8k. We replaced the thermostat housing and it helped quite a bit. I guess the housing was worn out and was allowing the coolant to bypass the radiator. Hope this helps
Just wondered what the score was on this problem?
Just got back on it yesterday actually. Customer put this on the back burner and had other stuff for me. However, I believe I figured it out yesterday! I decided to start checking into other systems besides the actual cooling system. I pulled the tranny dipstick and it was way, way over full. Which if I'm correct will make things run hot, and would explain why it stayed cool if you kept it in 1st gear. Then the customer informed me that it had been going through up to 2 gallons of motor oil a day. And when I pulled the tranny stick I knew immediately the oil was too black to be all tranny oil. So, looks like the torque is coming out and it'll be getting a rear main seal along with rear housing gasket. Thanks for all the input guys. Tranny level should've been one of the first things I checked but they told me multiple times that all other fluid levels were fine. And they've never given me a reason to doubt what they say. Pretty competent guys.
You'll know not to trust them next time when they tell you something .........
Might be worth looking at the tranny pump condition.Does it pick up ok from cold?. Experience tells me torque or scavenge pump will be seeing daylight soon,as you've pointed out.
Yes, the transmission works flawlessly Nicky.
I've been having a similar problem with my TD8E and will probably end up starting a separate thread. I am at the point of wondering if my sending unit or gauge are bad? I have done pretty much everything described above and don't want to hijack the thread, just wondering if i should try and replace these and see if solves it, or just start the thread now.
Have you checked the engine temp with a handheld temp gun? If there's even a chance the gauge or sender is bad I'd go ahead and replace it. That would be a cheap, easy fix.
When the gauge gets to the check line, i use a temp gun and it ranges from 210-220 degrees. Took the radiator cap off (safely under a thick towel) and used a deep fry thermometer and the coolant was at 190. If I use it for another 15 minutes the temp gun goes up to 230, makes me nervous. What's the limit? I am thinking it's the gauge because when the temp starts rising it goes up to pegged at a steady rate, doesn't slow down. Know of any online parts sources for an 86 International TD8E, no one around here carries anything and just about everyone I call isn't interested in helping me.
230 is over the limit in my book. I'd trust the temp gauge in this case. They'll read lower than the actual temperature if you're pointing at a shiny surface, but I've never seen one read higher. Does the temp gauge go back down if you let the engine run at medium idle with no load? that would indicate the gauge is accurate, and the engine is overheating. The coolant at 190 is no problem, but it sounds like you're getting poor water circulation if there's that much difference between the engine and the top of the radiator. What's the temp of the bottom of the tank when the engine is 220? If the engine is 220, the top of the radiator is 190, and the bottom is say 160, there's your problem.
Thanks, I'll start a new thread with all that I've done so far using this one as a reference. I'll run it up tomorrow and check the bottom and the gauge does drop when I let it sit at idle.
Drained 22 EXTRA gallons of oil out of the transmission. Runs cool as a cucumber now.
That'll do it ......... I bet the first thing you do next time (if there is a next time) is pull the transmission dipstick ......
Oh there will be a next time. Lol. And tranny fluid level will be the first thing I check.