Fox Help

[93fox85]

Not the best mechanic around by far but have some sense and experience.

Have a 93 fox. Inherited from a fam member recently passed. Its mildly built 302-bore to 306 and On3 Turbo kit installed. Trick flow heads, Megasquirt ecm

Out of nowhere, it started to overheat under normal easy going driving, so I shut it down.

Excessive pressure builds to the point the radiator has leaked.

No milky oil.. coolant and oil not mixing where I can see..no white smoke in exhaust...yet motor builds pressure and will overheat.

I learned the car doesn't have a thermostat. Bubbles from radiator that increase with temp increase of motor.

Chemical test was inconclusive

Head gasket? Water pump? Whats your thoughts.

Also. Heater in car not hot.

 

[nickyb]

When you say chemical test you mean you tested for head gasket leaks? If not you need to do that next.
You should have a thermostat in it,will give heat in car.
if water is circulating in radiator water pump is ok.
Does it build pressure while it is sitting,running at idle? In other words does it only overheat while driving?

 

[93fox85]

Yes I did the Chem test. Im positive I had coolant mix with the liquid.

Did another test later and verified no coolant entered the tube and the blue color did not change.

I bought a thermostat since when I got it. It didnt have one.

Also im replacing the radiator knowing it leaks so as for driving, I dont know it it overheats, however it does when idling in my driveway. When pressure builds, its enough where it will start seeping and spitting from the top hose at the radiator connection.

I've looked at all the pistons using a borescope and I haven't seen anything the makes me feel coolant has entered...no steam clean effect that I could see.

Thank you for helping.

 

[X-cam34]

Found a couple threads like yours and it seems to point to head gasket issue....

https://honda-tech.com/forums/acura-integra-6/bubbles-coming-radiator-but-lacking-almost-all-other-signs-headgasket-3369354/

Signs of Head Gasket Failure Related to Coolant - Fluid Life

Here are some top signs related to coolant that may indicate you have blown a head gasket and to get to your maintenance shop promptly!

www.fluidlife.com

edit:

https://www.jegs.com/p/Cometic-Gaskets/Cometic-Ford-302-351W-Cylinder-Head-Gaskets/2849515/10002/-1

https://www.trickflow.com/search/part-type/head-gaskets/product-line/trick-flow-by-cometic-mls-head-gaskets

• TFS-51694030-040 (Small Ford, 3.030" bore, 0.040" compressed thickness) or similar
• TFS-51494030-040 (Small Ford, 4.030" bore, 0.040") if you overbored to 4.030"

The Trick Flow/Cometic MLS line is solid for turbo applications. Call Trick Flow's support at 1-330-630-1555 to confirm the exact part number for your bore—they'll match it to your Trick Flow heads.

 

[nickyb]

You say it seeps/splits from top hose connection to radiator? Maybe its the clamp?
What temps do you get up to?

 

[Noobz347]

The chemical test should tell you whether there is combustible gasses mixed in with your coolant.

I am not clear on what you tested or how with what you've posted above.

Have you drained the coolant system? Is there any "milkshake" (oil in the coolant) in there?

What does your oil look like when you drain it?

What do your spark plugs look like when you pull them?

Do you have any codes in the EEC? Have you checked? You can sill have codes with no "Check Engine" light.