Operating Temp and Auxillary Instrumentation 302

During my educational overhaul of the cooling system on my '76 PCM 302 last year, I replaced or repaired most of the parts. Most were near the end of life anyways. Put in a new engine water pump, rwp impeller, hoses, Tstat (160 deg. from Skidim). Eventually found the culprit to be seaweeds in the trans cooler. After all that happened I found that the only time I get up to operating temp is when I am at WOT for several minutes. Pulling skiers or cruising I don't usually get above 120-130. I have verified the TStat opens up at approx. 160. The engine and trans both have coolers inline before the RWP.

1. Has anyone else experienced this? Should I try a different Tstat? I could restrict flow after the RWP but I don't like the idea of that.

2. Thinking about putting in a bank of auxiliary gauges. Some redundant and some new. Would like to measure oil temp, voltage, and additional water temp measurement. I was thinking about pulling water temp at one of the block drains since I already have valves there and could put a tee and plumb it easily. Where would be the best place to get an oil temp reading? I was thinking after the cooler but the easiest install would be off a tee I already have installed at the oil pressure sender.

Right now I have the oil pressure sender and a mechanical gauge on a tee. The sender I got pegs out the gauge as soon as there is pressure so I use that and a glance under the cover at the gauge to confirm good oil pressure. I'm sure it just an improper matchup between sender and gauge.


Looking for input from the veterans.

Thanks

Did that already. Confirmed the gauge is reasonably accurate and the engine is running cold.

A picture or 2 of the engine showing the cooling system from the front would be a good idea too

wiscofoot wrote:    The engine and trans both have coolers inline before the RWP. Thanks

Do you know anything about the cooler for the engine? Did a PO add it? It's an oil cooler correct?

Or photobucket... seems to be working again now with big watermarks

No (engine) oil coolers on any pcm’s I’ve ever seen that I can recall. Do you mean transmission cooler?

I wouldn’t expect an appreciable difference in engine operating temp with a cooler in the loop anyways... suspect something else is going on. No holes or anything drilled in the thermostat, are there?

TRBenj wrote: No (engine) oil coolers on any pcm’s I’ve ever seen that I can recall. Do you mean transmission cooler?

wiscofoot wrote:    The engine and trans both have coolers inline before the RWP. Thanks

TRBenj wrote: I wouldn’t expect an appreciable difference in engine operating temp with a cooler in the loop anyways...

I wouldn't expect any appreciable engine temp differences ether. The reason I asked is maybe a PO has been messing with the cooling system. I hope some pictures will give us a clue.

TRBenj wrote: No holes or anything drilled in the thermostat, are there?

No holes in the Tstat that is installed. I have seen recommendations for doing that on other forums and ones for sale marketed as "offroad/racing" that come with holes predrilled.

Link for TStat that's installed-

https://www.skidim.com/prodinfo.asp?number=RP026002

Got frustrated trying to solve the overheating and decided to stop using autozone t stats, and shortly after installing it I found the weeds in the oil cooler.

Hopefully can get pics tonight but I am not going to be running the engine for at least 2 months so I will put this engine temp question on the back burner for now, maybe. I'm quite sure there is an oil cooler on the raw water suction that is NOT the trans cooler. I remember using a 24" piece of hose to connect it to RWP.

Curious why you guys think that an oil cooler wouldn't have a significant impact on engine temp.

woodyelc wrote: FYI.   The engine oil cooler came on that motor as stock from PCM. .

Woody,
Which engine is that?

wiscofoot wrote: Curious why you guys think that an oil cooler wouldn't have a significant impact on engine temp.

More water flows through the engine compared to oil. Also water jackets are located closer to the source of heat

woodyelc wrote: Look at the manuals in the reference section and that cooler was used in 74 and look at the other manual middle picture you will see the oil cooler.

Woody,
How about a link. I looked and I'm not finding the picture.

8122pbrainard wrote: woodyelc wrote: FYI.   The engine oil cooler came on that motor as stock from PCM. . Woody, Which engine is that?

KENO wrote: Pete Your search skills are kinda crappy today

Thanks Ken. I wasn't thinking Waukesha since Woody mentioned PCM.

8122pbrainard wrote: 8122pbrainard wrote: woodyelc wrote: FYI.   The engine oil cooler came on that motor as stock from PCM. . Woody, Which engine is that? KENO wrote: Pete Your search skills are kinda crappy today Thanks Ken. I wasn't thinking Waukesha since Woody mentioned PCM.

I got that same manual with a 76 SN back in 77 and spent a fair amount of time trying to find the non existent engine oil cooler. The boat had a PCM with an older Waukesha manual.

I seem to think that was back in the "tight money days" for CC

I did see one with a cooler at the dealer way back then. It was around a 73 or 74 on a 351

Ken,
What do you think? I have a feeling phone company trucks and police cars had oil coolers because the drivers of them sat in the AC all day long on those hot days!

In the 90's we didn't have GPS so we didn't need air. We drove back to the central office and hung out there. It was cool in the summer and warm in the winter Then around 01 we got GPS and soon after all the new Chevy's had air. Turns out they didn't do it for us but it cost them money to delete it. The GPS kept track of how long the truck ran and they would let you know weekly how long your truck was running.
I think I actually hold the unofficial record for the coldest temps and the least run times. Our boss used me as an example one week at around a half hour of idling time. I got alot of dirty looks from the rest of the crew because they knew what the boss didn't, I had an electric heater in the cab and ran the bucket generator all day It was actually better because I could lock up the truck and leave it as I worked and didn't have to worry about the keys being in it.