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Author Topic:   RADIATOR PRESSURE
fastrack1
Member
posted May 09, 2004 07:49 PM
I am having a brian spasm .Having a cooling problem .In the past i was thinking if a system held pressure for a certain length of time like 2-3 days everything was ok .Now after running in the shop for a length of time it builds no pressure.Change caps still same problem .It is pushing the water out in about 10 laps .I suspect a cracked head but dont see any evidence in the exhaust ports or discolerd valves unless it could be a intake .IT had been cool till 2 races ago

[This message has been edited by fastrack1 (edited May 09, 2004).]

juliaferrell
Member
posted May 09, 2004 09:20 PM
Are you sure water is circulating? No circulation no pressure...............hope that helps.


racer17j
Member
posted May 09, 2004 09:26 PM
do a compression check and see if you have a head gasket bad


smallrock98
Member
posted May 09, 2004 10:41 PM
Your building no pressure??? WOW, I am having the opposite problem. I am building too much pressure and it is pushing all my coolant out of the overflow before I even get up to temp. I have already changed the head gaskets but that didnt fix the problem. Only other thing I can think of is that my radiator has some kind of problem.


fastrack1
Member
posted May 10, 2004 03:55 AM
Have done a compression check.Every thing checked ok .Water is circulating like it always has .


juliaferrell
Member
posted May 10, 2004 09:41 AM
If you induce the cooling system with compressed air do you think it is capable of holding pressure? Put the cooling system under pressure and see if it leaks off? Just an idea?


awkwardjeff
Member
posted May 10, 2004 01:18 PM
will all the new users joining this forum some things are repeated annually. This being one of those subjects. Buy a leak down tester..... cost is about $65 back off all the valves and remove all plugs. Thread leakdown tester into spark plug hole and hook up to air supply.... set at 100 PSI this is your air supply going in....open vavle on leak down tester and check gauge. If the 2nd gauge (this is a dual guage tester) reads 90........you are leaking 10 percent......if it reads 80 you are leaking 20 percent..... this will tell you if your rings are sealed, valves are seated, or leaking compression into the water system. You will need to remove rad. cap...... if you have air bubbles you will see what cylinder has the problem.


TRM38
Member
posted May 10, 2004 10:50 PM
Thats where its going for sure, even with the high pressure cap you still need an overflow can.



bigcitycowboy
Member
posted May 20, 2004 07:55 PM
im having a similar problem. i just purchased a stewart pump(stage 1) high pressure rad cap(morroso 23-25) griffin 2 core alumuin radiator, good shoruod and 1 to 1 pulleys, and NO restrictor(per stewart). im having problems getting HOTT!!! it can idle for hours, nevers gets above 150. plenty of air traveling threw raditor. running 36 degrees total advance, and plugs are fine. now i know its building alot of pressure , cause its blowing by the radiator cap. and i also did a pressure test, pumped up the system, and its loses pressure somewhere. cant find no leaks. oil is good, and did compression test, everything is good. 1 & 3 are little higher (like 10lbs) but dunno where pressure is being lost. please help. thx jeff
SORRY SO LONG


dirtracer14
Member
posted May 20, 2004 09:26 PM
I have had the problem that some are talking about with the gauge not saying its hot and having it push by the cap!!! It was the gauge...put a new one in and found that i was running HOT and it was not reading on the gauge....dont assume the gauge is good...its pretty easy to replace...if you have a tire temp gun check the intake and block and so on.....when its running and its only 160 can you put your hand on the head or is it to hot? The other thing is that if you have a air pocket in the block it will do lots of weird things....just a few things to help.


tech355
Member
posted July 20, 2004 10:51 PM
make sure your temp sending unit is not mounted in the water pump, this will cause a cool reading.


fastrack1
Member
posted July 21, 2004 07:39 PM
PROBLEM SOLVED 2 CRACKED HEADS IN THE INTAKE SIDE OF THE VALVE SEAT. GOOD THING WAS GOT PROTESTED FOUND LEGAL AND PICKED A LITTLE EXTRA MONEY TO GET THEM FIXED .


marshalr
Member