20min Overheat

[EastBoundJoe]

Hello again, the midget over heats every 20 minutes or so when driving. After stopping you can hear the fluid bubble in the over flow tank (this is a 1275 engine) and see a small amount of white smoke coming from the oil filler cap (hot or burning oil). When the previous owner drove it to my house he had to keep refilling the radiator with fresh water because it would evaporate while driving.
I know there are several causes to an over heating engine, such as:
• Low coolant level
• Restricted radiator
• Stuck Thermostat
• Late Ignition Timing
• Loose Belt tension
• Bad water Pump
• Exhaust Blockage (not in this car)

I installed a new overflow cap, the previous owner installed a new thermostat, https://eastboundjoe.tripod.com/imagelib/...&target=tlx_new

I put the thermostat in hot water today and it opened up before boiling point. When running the car I felt the upper radiator house (connects to the thermostat), squeezing it I felt no real pressure. When taking off the upper house it was not filled with any fluid, next I removed the thermostat and to my surprise I found antifreeze in the block https://eastboundjoe.tripod.com/imagelib/...&target=tlx_new

I though that the whole system was running off of water because that is all I have (and previous owner) been putting in the system lately. I suspected that the thermostat was stuck because the water and coolant have not mixed, but the thermostat opened when sticking it in hot water (not sure how high the temp was). Not sure if the coolant from the block is reaching the radiator. There is no squealing coming from the engine belt when running so the belt should be tight enough. There isn’t any water or antifreeze leaking from the water pump.

I’m thinking there could be a restriction some where in the radiator (the DPO gave me a spare radiator) I’m going to have the radiator cleaned out by an HVAC buddy of mine then re-install and see if that helps anything.

Your thoughts? Any Ideas of how to trouble shoot this sort of problem?

 

[SilentUnicorn]

lets not forget proper bleeding of the system. An air bubble can get trapped and prevent circulation. least i know it can on a 1500.. the 1275 crew will be along soon enough


mark

 

[sparkydave]

Agreed, sounds like it's got a wicked air bubble trapped somewhere. I've succeeded in burping mine by disconnecting heater hoses temporarily as I filled it, but hopefully somebody more familiar with 1275s will chime in. In the meantime, I wouldn't run it if the water pump doesn't seem to be pumping, it really trashes the seal.

 

[Sarastro]

If you're losing coolant, it's not by evaporation. Liquids don't evaporate from closed systems; it's leaking somewhere. You might also have some other problem, but if you can't keep the thing full, this is something you have to fix, in any case.

Thermostats are cheap--I'd just replace it. Then, make sure the hoses are good and not kinked, radiator is clear, and except for the possibility of a bubble, as noted by others, it really should be fine.

 

[zimasprite]

You sure the water pump is working?

 

[spritenut]

Make sure the water pump is pumping by looking in the radiator when it's at temperature. If it is pumping, and you are loosing coolant and there is no sign of a leak, you have a blown head gasket.
I just went thru the same scenario. Bad gasket between #2 and a water jacket. I was burning the water out of the engine but the car still ran fine, I was also pushing compression into the radiator. If you run the car for a few minutes from cold, and then carefully remove the cap and it shoots sky high, you are pumping compression into the colling system.

 

[bugimike]

Bad head gasket would fit most of the symtoms you describe, from overheating to losing coolant to fumes from the oil cap. What does the oil look like on the dip-stick? Gray and sludgy means water in the oil and it is definitly a head gasket (though a bag gasket won't always put water into the oil!)

 

[EastBoundJoe]

The dip stick is not gray it looks the normal dark-brown color.

I ran the engine today with and without the thermostat looked down the radiator while revving the throttle found that the water in the radiator moved down and when I let go of the throttle it came right back up. I took a picture of the thermostat housing while the car was idling (no thermostat in the housing).

https://eastboundjoe.tripod.com/imagelib/...&target=tlx_new

I’m not sure how much is supposed to be pumped out, but before doing this I brought the car up to operating temp. I would think a lot more is supposed to be pumped out seeing there is no thermostat installed, either way the coolant/water does not seem to be moving through the entire system very much. I also blew in the heater core hoses and noticed the coolant at the thermostat pushed out just fine, but while squeezing the lower radiator hose the fluid at the thermostat barley moved.

https://eastboundjoe.tripod.com/imagelib/...&target=tlx_new

If there was a bubble in the system how would I purge it?
What should I check first the head gasket or the water pump?

 

[EastBoundJoe]

I feel like an idiot for posting this but I think I found the problem, after taking off the radiator I gave water pump a spin; the video explains it all

https://www.youtube.com/watch?v=Zg2advm8xwM

I bet that could be the reason for only a small amount of fluid being pushed from the block to the radiator. /bcforum/images/%%GRAEMLIN_URL%%/crazy.gif

 

[bugimike]

I think that video says it ALL!! /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
Pump's gotta turn to do anything!! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

 

[Sarastro]

Still doesn't explain the loss of coolant. It has to be going somewhere. If it's being lost through a failure in the head gasket, you should be seeing lots of white smoke from the exhaust or lots of water in the oil. If it's a leak, you should see it...leaking!

If it's disappearing and you don't see any of these, something is really, REALLY strange. Sometimes small radiator leaks open and close in response to temperature changes or crud plugging them up. Even if you don't see a leak, look around for signs of previous leakage--like, for example, water tracks in dirt.

 

[EastBoundJoe]

There is no white smoke coming out the tailpipe, it is clear.

The fluid looks like it is draining out of the expansion tank where the overflow hose is. I filled up the tank last night drove it then smelled antifreeze it was coming out of the expansion tank I looked in the tank this morning and it was empty.

I think the expansion thank hoses may be switched around but I’m not sure, take a look
https://eastboundjoe.tripod.com/imagelib/...&target=tlx_new

It was leaking out of the lower hose, purple color in the pic.

 

[SilentUnicorn]

Hard to tell from the pic, but the hose on the top of the bottle should be the overflow hose.

mark

 

[bugimike]

purple hose should attach where red hose is attached! What does red hose go to?

 

[lesingepsycho]

If you are putting nothing but water in your engine as you say, you are going to blow your head gasket. YOU ABSOLUTELY MUST have anit-freeze/COOLANT in your mix!!! PLEASE, for the love of all that is automotive, put some anti-freeze in! If you and DPO have been putting nothing but water in, you should probably put a minimum 2 gallons in. Drain down the system if you have to in order to get that much in. I don't care how much water you put into a spridget, the cooling system isn't efficient enough to run straight water. In fact, most cars aren't but ESPECIALLY spridgets.

For a refresher, anti-freeze/coolant lowers the freezing point and RAISES THE BOILING POINT. I would really not be surprised if more than half of all spridget over-heating problems could be attributed to insufficient coolant mix.

Please believe me. My dad toasted more than a few midget head gaskets, I toasted one, and nearly toasted a 1966 Ford Mustang all because my dad and therefore, I, never understood anti-freeze/coolant and how it works. He was the kind of guy who always carried the spare jug of water and that was all he ever put into an over-heating system and the problem would get worse and worse until something finally blew.

Please save yourself the trouble of learning that lesson the hard way!

JACK