High Oil Pressure, High Temp?

[HondaEater]

What is the flow pattern of the cooling system for a 2.8?
The lower rad hose of my truck isnt getting hot all of a sudden,
im trying to figure out weather there is blockage in the system, the
thermostat is getting stuck, or worse, possibly a headgasket.

The oil pressure gauge is reading high too, that's why i fear the headgasket(s)
may be slipping.

Going to do a compression test tomorrow, and pull the thermostat to see if i can solve the problem, just trying to get this thing fixed, it's my daily driver. Thanks

Also, i have the thermostat on the upper hose, not the lower. The upper hose is warm as well as the bypass, but the lower hose is not

 

[AllanD]

the t-stat is in the lower hose on a 2.8

 

[HondaEater]

i believe ive read some came with it in the top, and some came with it in the bottom? either way, that doesnt answer my question or help solve my problem. but thanks for the input (im not being sarcastic or a smartass)

 

[adsm08]

the t-stat is in the lower hose on a 2.8

ewwwwwwwwwwww

 

[HondaEater]

Any suggestions? I'm pretty sure the tstat is on the upper hose

 

[HondaEater]

Can i rule out the headgasket(s) it wouldn't make sense that one or both of them would be slipping, cause if so id still have pressure in both hoses, right?......

 

[snake]

Not sure about the headgaskets on this one. The lower hose is supposed to be cooler because the hot water comes out of the top of the engine, goes down through the rad, and back into the engine. So That's cooled off water going in the bottom. I would get a laser thermometer and see what temps you are getting on both hoses. That top one should be as hot as the thermostat you have, which is probably 180 or 195 just guessing. Bottom one could be zero, doesn't matter. How do you know it isn't flowing? I'd pull the cap off the rad, warm it up and watch. Should start flowing when the T-stat opens, and as long as the water going out is hot enough, but not too hot, I wouldn't worry about the rest of it. As far as building up pressure? Some just don't seem to build up and others will swell the hose pretty tight. The rad cap is what holds pressure, so try replacing that if it is a concern. If you see bubbles in the rad when running, that is likely an indication the head gasket could be gone. If the truck isn't overheating, I'll bet it is fine...

 

[feellnfroggy]

Its my understanding you can get two kinds of thermostats. The older ones came where if they went bad they went bad closed. But the newer ones blow open so water can keep flowing. If you have a cool lower hose, then you possibly have no fluid or a blocked passage....

 

[HondaEater]

I popped a turkey thermometer in the rad after a 13 mile drive home ( i dont have a laser one, the snap-on dealer at my shop has been bullshitting on getting everyone their tools anyway) and it read 160F...lower rad hose is still not warm.

ive replaced the rad and all of the hoses in the coolant system, and the cap. it wasnt..the upper rad hose doesnt feel extremly hot, just warm. maybe its not overheating and the gauge is just freaking out? it is 25 years old....

 

[Jon Boy]

the t-stat is in the lower hose on a 2.8

my old 84 with a tk4 was infront of the intake. my hayne's manual says some 2.8's had low in front of the eng.

your the tech advisor where were you on this one.
EDIT: oops, i just realized you said hose i was thinking on the engine side, your talking on the rad side. lol

 

[igiveup]

Hello

The 85 2.8l the T-stat is on the upper hose. It is on my 85.

igiveup

 

[HondaEater]

I'm going to pull the thermostat and run without it for a day, maybe its stuck closed?

 

[feellnfroggy]

If its stuck closed then its no good. Youll be pulling it out, rtving and putting a enw gasket to close it up without a thermo stat and then doing it all over again. Probably best to just replace the thermo stat with a new " blow open design" an dnew gasket and get it out of the way, its not a very expensive part. Then you for sure wont have to worry bout it anymore.