135hp Chrysler overheating.

[cacookie]

Overheat buzzer is sounding after a couple off minutes use. I have replaced the impeller and it is pumping water out thru the exhaust and the outlet at top of leg. Removed the tell tale screw from top off block, and no water coming out at idle, and only a gurgle coming out at half throttle. when i checked the thermostat it didn't have one installed. is there any thing i should be looking for.
Thanks.

 

[moparman]

Re: 135hp Chrysler overheating.

If the motor has been sitting for a while dirt daubbers will build nest in the water passage and stop up the coolant flow.You might want to check your flow from the bottom leg to the upper block for restrictions.Keep us posted on what you find. MOPARMAN ROLL TIDE

 

[cacookie]

Re: 135hp Chrysler overheating.

Sorry mate, i'm from Australia and don't know what dirt daubbers are. 8 weeks would be the longest period without a start up during winter, gets run most weekends during summer(which is now for me). When i had the leg off checking the impellar, i run the garden hose up the water intake and had plenty off return flow. The only thing i can think off is that the passages thru the block are blocked and only part off the block is getting cooling water.

 

[Frank Acampora]

Re: 135hp Chrysler overheating.

If you can get it off without stripping or snapping the bolts, remove the bypass cover and see if the plastic bypass valve is stuck open The cover is the small diamond shaped piece about 1 x 1 1/2 inch, held with two hex head screws. It is located at the bottom of the block in the dogleg of the exhaust cover.

These valves get a lot of corrosion. they are normally held closed by spring pressure but if the cover has corroded to the point where the spring has lost most of its force, the valve can open too easily, allowing water to bypass from the block inlet to the exhaust leg.

Thus, cooling will be fine at idle and low power, until you go to higher throttle settings. Just another thing to check. Thet were removed on late Chrysler and Force blocks--not needed.

G'Day mate!

 

[cacookie]

Re: 135hp Chrysler overheating.

G'Day mate!

G'day Mate

I will check out the bypass valve tonight. When i was checking the thermosat i broke 3 of the 4 bolts.

 

[cacookie]

Re: 135hp Chrysler overheating.

Hi Frank, I checked the bypass valve tonight, The spring seems O.K but the valve is stuck in there. Is it better to have it permantly in or should i try to remove it all together.

Thanks Mate for your help.

 

[Frank Acampora]

Re: 135hp Chrysler overheating.

Better to have it permanently closed so no water bypasses the head. As I said, in later engines, it was eliminated. However, if it is corroded in that badly, you need to remove it and clean the bypass port itself. Corrosion may be blocking some of the supply tube. If you can get the exhaust cover off without breaking bolts--not very likely-- then cleaning the water passages in the block would be the next step. HOWEVER: It is MOST likely that you will snap at least a couple of the bolts and you know what a pain it is to drill them.

So before you start doing these things, it pays to go back and check the water pump to be certain it is delivering full volume.

Then, maybe you might have some luck removing the head and cleaning the water jacket around the cylinders.