overheating

[79cjBEAST]

1041023

anyone who can help? i have a 79 cj7 3 speed with a AMC 304 stock. recently i replaced the carb witha new edelbrock 4 barrel square series, engine is running great but seems to overheat quickly. popped the hood and noticed the main hose runnin to the intake manifold is swelling as if the engine doesn't breathe enough coolant when driving. Could this be a thermostat prob? i seem to think it is more than just that, not knowing too much bout jeeps. could the problem be the water pump? i just put a new radiator on it but could it be not big enough for my new carb. Lost, and waiting for any help anyone can provide. Thanx![addsig]

 

[hi_c]

1041025

Well, I've only got a 4cyl in my 89 YJ, but I've had to replace my radiator, water pump, and thermostat all in the past 45 days. The hose running to your intake manifold that is swelling... does it come from your radiator? If so, then it is probably not going to your intake manifold, that's for air. The Intake and water pump are usually close by and if that swelling hose is coming from your radiator, then it's going to the water pump and it's not cycling it and pushing it back to the radiator. I would say that the Water Pump is your problem. If/when you buy a new water pump (relatively cheap, mine was $13 remanufactured) be sure to go ahead and buy new hoses. They are also relatively cheap, and you'd hate to replace the water pump and then 4 weeks down the road, one of your old hoses busts and you gotta get back in there. Do it all while you got it open. The thermostat is usually $5 too. Replace it while you're at it. If you have a Haynes manual, you should be able to get it done in one day. Have a buddy help you! 2 heads are better than one.

[addsig]

 

[79cjBEAST]

1041026

thanks for your thoughts...maybe i should clarify this hose goes from the top of the radiator to the intake manifold where it bolts on over a thermostat. I took out the thermostat to see if that was the problem but the hose still swells when i drive around. to me it sounds like the water pump isn't working i just wanted a little more expert opinion, than what i beleieve. Thanks for any help![addsig]

 

[berettajeep]

1041027

replace your Radiator hoses top and bottom,your heater hoses,thermostat,water pump.Get new anti freeze add it at 60%coolant 40%water. All this stuff should be about $100. This is simple to do,if you have not done it before.[addsig]

 

[jprtroy]

1041115

Think about this. What is causing the hose to swell? If the water pump is working, you'll be able to see coolant move in the top tank. You'll want to check this with a cold motor! NEVER REMOVE THE CAP WHILE THE MOTOR IS HOT! With a cold motor (cold coolant) you can run the motor with the radiator cap off, (with safety glasses/goggles on) you can see coolant moving through the cap opening. There's a bypass in the thermostat housing that allows a restricted amount of coolant to flow continusly. Only when the the thermostat open will full flow begin, but a tiny flow should be seen.

If the thermostat remains closed (stuck) the coolant flow has no return. This might cause a build up and cause the hose to "buldge" in a weak spot.

Unless you see signs of the water pump being bad, I.E. water leaking from it's weep hole, chances are it's fine.

I've seen this happen in the past, the wrong water pump installed. My jeep uses a reverse rotation pump. I don't think a reverse rotation pump is a problem for your motor ( might not be made for it not sure I know the 6cyl) but, they are made for my 6cyl!

Sounds like a weak hose. As mentioned, replace all the hoses.

[addsig]