What's up guys? I'm having alittle problem w/ my cooling system. It seems that when I'm driving and I really get on the gas (Floored for 5 seconds or so...) the radiator overflows and dumps all the extra coolant into reservoir container which eventually overflows causing a huge mess. (picture me sitting at a traffic light and antifreeze dumping out over my driver's side front tire) This has happened approx. 20 times. At first I though I overfilled the radiator....Nope. I checked the radiator and it was almost empty. And the engine temp is normal...190.
This all started after I installed the supercharger. I'm currently running a heavy duty radiator (1 year old) Milodon high volume water pump, a new Milodon 160 thermostat, new radiator cap, and I even bought a new coolant resivoir/windshield washer container because the 2nd time this happened it blew the side seam out making it useless.
Hopefully I'm overlooking something......any input would be great.

Thanks,
Jerry D.

 

hey I am haveing the same thing happen to me but it is on my Mazda MPV 2000. Only it not when I floor it, it is when the engine is hot and I take off the radiator cap.

 

Your not supposed to take off the cap when the engine is hot...

Really only two things will make the radiator overflow like that, it is either overheating or is becoming pressurized - by a leaking head gasket for example, you would probably have other symptoms if that was the case though. When you say heavy duty radiator do you mean a heavy duty towing radiator? That may still not be enough for the kind of horsepower and heat your engine is making, you might need something like a 4 core Griffen. I'm not sure how accurate my temp gauge is but my truck only runs at 175 degrees with a 160 degree t-stat.

-Jon

 

Yeah it's just a stock heavy duty rad. by an aftermarket company. No prob w/ the temp.....195 200 w/ the A/C on full blast.

I hope it's not a head gasket!

 

you can dye test the coolant to see if combustion gasses are present. this will determine if the head gasket is leaking.

also pressure test the radiator and see if coolant gets into the engine oil or cylinders. pull the plugs first to see if any get in the cylinders.

 

Good thinking!
I think Napa sells a coolant test kit to indicate hydro carbons.
I will keep you posted.

Thanks!

 

Im betting its a head gasket.

It starts after a few seconds.....Just enough time to build up boost pressure.


I bet if he takes the belt off of the charger, the problem will go away or at least improve.

He said "

I got $500 that says its the head gasket. Its almost impossible to cause a radiator to over heat and boil over in 5 seconds.

 

Thats what i was thinking, try driving it without the supercharger belt, the high boost pressure might be pushing past the head gasket. Careful with those dye testers, my experiance is that they aren't very accurate, i prefer a compression test or a cylinder leak down test.

-Jon

 

* UPDATE *

Well, I guess it's time to install new head gaskets! The test showed some signs of hydrocarbons in the coolant.
So, the question is what head gaskets and intake gaskets should I use so this does not happen again. I'm pretty sure they make special gaskets for blower and nitrous applications.
Please any info would be helpful......this is my 1st supercharged vehicle.

Thanks,
Jerry

 

on my n2o fed stang i use a Fel-pro Loc Wire® head gasket. the head needs machined to accept a lock ring though.
I've never had a problem in the last 8 years with them. I'm sure there are other types out there that don't require the machining done.

click here for Fel-pro head gasket info

 

Summit racing or Jegs should be able to help you out there are special gaskets designed for high boost pressures. A lot of people swear by Cometic multi layer steel head gaskets, i'm not sure what applications they are available for though. Looking at my summit catalog right now they have some copper head gaskets rated up to 43 psi boost.

-Jon

 

The biggest problem with boosting your engine isn't so much the head gasket material, it's the fact there aren't enough head bolts (10, as opposed to 17 for a SB Chevy). You can try head gaskets made of different material, but as long as the heads are off, I strongly recommend having them machined for Loc Wire gaskets, like lees99f150 suggested.

 

That is a good point about the head bolts. If your not using them already you might want to pick up some arp head bolts or studs to make sure your getting the best clamping force that you can. I know of a few built 351W motors running 2 stages of nitrous (250hp total) with copper head gaskets without problems. Copper head gaskets are a little bit prone to coolant leaks but i've heard of locwire gaskets causing problems also. I have been using Mr Gasket Victor Reinz series gaskets without problems but they are still a fiber gasket that probably wouldn't like boost. High horsepower engines are high maintainence but thats part of the fun! I love replacing my gaskets and valvesprings every winter!


-Jon

 

We used to tear down the engine in the sprint car every winter, but got lazy after last season. We just tore down the top end, and it's been fine so far. This is the last season for that block, though. lol. It's held up rather well for a 700hp n/a small block Chevy, though.

 

purdy....