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Topic: 1987 Grand Villa Cat 3208 oil operating temperature (Read 1463 times) previous topic - next topic

1987 Grand Villa Cat 3208 oil operating temperature

Hello,

I'm new to this forum and am excited to get some expert opinion.

I have a 1987 Grand Villa in excellent condition,  75,000 miles.  It has a Cat 3208 engine, Allison 4 speed auto trans.  We live in Oregon just above sea level. We just took a trip to southern Utah and experienced a number of changes and i need to know if these are normal.

Engine water temp runs 160 to 170 normal, sea level and at altitude when pulling flat.  At altitude,  when pulling a steep grade it will run up to 180 to 190. Oil pressure runs typically at 68 to 70 lbs (two gauges, mechanical and electronic), drops to 65 - 60 when pulling a grade.

Oil temp is my question. I measure at two positions, two gauges. The factory t-sender is located on the back of the left cylinder head,  at the end of a cross over house coming from right head (looking at back of engine, front of motor faces rear of coach). I installed a second gauge with the t-sender located in the pan. Both gauges are new Stewart Warner gauges.  Depending on outside air temps the Pan temp runs 180-200 +/-5 normal sea level and at altitude, 210 - 220, (maybe 230) when pulling a long steep grade.  Head temps however run 195-240 normal at sea level and altitude, "250-290" (?!?!) pulling a steep grade. Again,  water temps seem normal; all gauges and temp senders are new.

Question; should I be concerned about any of these oil temps? What is too hot? When should I be concerned?

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #1 –
I would not be concerned on the higher head temps "under a heavy load" your coolant temps indicate the system is doing its job.

Now if your pan temps stay that high i would be concerned.

IMHO

Hans

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #2 –
When pulling a steep/long grade those temps are not unusual. You don't want your engine running at those temps for very long. (if at all!) Your engine is telling you that you are working it too hard. Slow down and down shift to keep the temps below the 210º-220º mark. Preferably the 210º mark. All those trucks you see in the right lane on the hills are there because they are doing the same thing you are. Pulling a lot of weight up a big hill. This takes a lot of energy that is consumed as heat. If your cooling system can't get rid of that heat your only choice is to slow down and use a lower gear.

EDIT: my post is mostly about engine temp. If indeed your engine temp is staying below 190º I agree with Hans. Your engine is running as designed.

see ya
ken

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #3 –
I'd never want to see oil temps over 270. On all engines, sump temps are usually higher than anywhere else in the system, because the oil is cooled via the oil cooler after being pumped, so the sump should be the hottest part of the system, as that oil has just returned from much hotter parts of the engine and is carrying heat away. This is especially true on turbo engines, with turbo bearing cassette heat and piston oil cooling jets. 

I'm wondering about the accuracy of the head gauge... maybe it is picking up extra heat from the exhaust manifold or something causing it to report higher? 290 is going to affect the life of the oil, and your engine... not that that is much of a concern on a 1987 with only 75k miles... but I'd trust your sump temps more. if the oil is 290 at the cylinder head and only 230 in the sump, where is it shedding that 60 degrees?

Or possibly your sump gauge is not accurate.. in the air cooling it? unless the sender is sitting IN the pan and IN the flow of oil on the head, both could be suspect.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #4 –
Quote from: car54 –
I'd never want to see oil temps over 270. On all engines, sump temps are usually higher than anywhere else in the system, because the oil is cooled via the oil cooler after being pumped, so the sump should be the hottest part of the system, as that oil has just returned from much hotter parts of the engine and is carrying heat away. This is especially true on turbo engines, with turbo bearing cassette heat and piston oil cooling jets. 

I'm wondering about the accuracy of the head gauge... maybe it is picking up extra heat from the exhaust manifold or something causing it to report higher? 290 is going to affect the life of the oil, and your engine... not that that is much of a concern on a 1987 with only 75k miles... but I'd trust your sump temps more. if the oil is 290 at the cylinder head and only 230 in the sump, where is it shedding that 60 degrees?

Or possibly your sump gauge is not accurate.. in the air cooling it? unless the sender is sitting IN the pan and IN the flow of oil on the head, both could be suspect.

I believe what is happening is that the oil from the head then drops down to the cooler which is directoy below the left head. So I think the path is sump, block, heads, cooler, and then back into the sump. Once the grade has been crested both water and sump temps drop first and fastest, head temps drop last and slowest. BTW the head t-sender is in the factory location, very close to the turbo. The sump temps never range higher than stated.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #5 –
no sorry, you are dead wrong on that. the oil pump picks up oil in the sump, which first visits the cooler and  oil filters before going further. all oil is filtered and cooled prior to doing any lubricating in the head, bearings, turbo, etc.

Consider this: how would it flow thru the cooler after it has done its job lubricating? it gravity drains back to the sump, it does not gravity drain thru a restrictive cooler.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #6 –
Quote from: car54 –
no sorry, you are dead wrong on that. the oil pump picks up oil in the sump, which first visits the cooler and  oil filters before going further. all oil is filtered and cooled prior to doing any lubricating in the head, bearings, turbo, etc.

Consider this: how would it flow thru the cooler after it has done its job lubricating? it gravity drains back to the sump, it does not gravity drain thru a restrictive cooler.

Car 54 thanks so much for your input. The sump t-sender is "in the pan" itself. I had a hole drilled and a bung welded on to the oil pan with the correct threads. The t-sender screws into this with the tip of the sender being in the flow of the oil in the pan. The upper t-sender however is a different story. It screws into a 6 way fitting mounted on top of the left head, in relative range of the turbo (and it's heat) that is fed by the hose coming off of the right head. Oil pressure (mechanical and electronic), temperature ... which we are discussing, the feeder hose itself and 2 plugs occupy the ports on this fitting. There is no "return" hose going back to the engine. So "flow" to this point is poor at best. I think any true value of oil temp from this set up is suspect at best. However, this is how it was set up from the factory. The stock gauge (which only had a "green" range - good, and "red" range - PANIC!) never even moved unless you were pulling a hill. So I replaced it with the current new gauge and sender which isn't providing any less sense of panic.

Given your input and that of others, do you think it reasonable to come to the following two conclusions?

1. Since the sump temp is coming from the flow of the oil itself at it's hottest point (to your point) then this temp is the one I should care the most about.
2. Since the engine coolant temps continue to run at an acceptable range (160 - 190) there is no unacceptable over-heating occurring to the oil (which would cause overall coolant temps to rise).

Please let me know your thoughts.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #7 –
To verify that you do have the correct engine thermostat (Caterpillar calls them "regulators") please call the Caterpillar RV Hotline with your engine serial number: 877 777-3126.

It is possible that 160 degrees F is too cold.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #8 –
Based on your description of the mounts, the sump sounds like a far more reliable location for temps than a sending unit with very little flow. In this case, based on your sump temps, I believe you are OK. I dont see anything wrong with your coolant temps either. 160-190 is a good safe range, higher temps give better economy, but for an old cat, I dont think 160 is problematic.

Re: 1987 Grand Villa Cat 3208 oil operating temperature

Reply #9 –
My 1990 250hp 3208T runs coolant temp of 160 degrees--- I haven't seen it vary more than 10 degrees.  Oil temp stays pretty close to coolant temp, maybe a few degrees higher.  That said, we don't have too many long grades around Galveston, Tx., but we do have high ambient temps.  The Atlas radiators that Foretravel used on the 1990 Unihome with the Cat 3208 was a monster unit--- no cooling issues at all.