Overheating 351W -Help!!

On Fri, 04 Sep 2009 15:25:57 -0400, tom rearranged some electrons to say:

Does the heater blow hot air?

Did all this start when you changed the t/stat? Maybe a bad t/stat, or installed upside down?

Wouldn't be the first time I've seen that either!. Most of them come with a picture of how to install it, but, us real men usually ignore specific instructions like that. We are mostly more accustomed to following our wife's instructions!

It would probably be a good idea to just bite the bullet on the Tstat and replace it again anyway - not a hard job just to make sure.

Lugnut

No, I'm sure it was in right. I'm going to try running without it just to see what happens,

Any chance it's got a blown head gasket, maybe just a tiny leak? Are you running 50/50 antifreeze mix or straight water?

Was 50/50 until I began working on the problem. Now it's straight water for the interim.

I used that NAPA test kit for head gasket leaks- the blue turns yellow if combustion gases are present. It stayed blue.

Tom

If you installed it backwards, upside down, or it was defective out of box, this could still be a problem.

I'd not expect this to be a problem unless the main issue was that the radiator does not seal.

You probably erred in roughing up the surface of the pulley. This is hazardous to the long life of the belt, but would not cause the problems you are reporting.

This does not play into your problems at all.

The Fan Clutch would cause a symptom of overheating at idle -- heavy stop-n-go traffic -- but the overheat would go away at sustained speeds above about 40-ish.

This would not play into the symptom set you describe UNLESS the engine is running poorly too, in which case you can have a wire or two crossed, and the timing is out of whack. I'd expect you to report poor running as the main problem though, with overheating as a sidebar.

Given the symptoms and repair steps already attempted, I'd be looking at the t-stat again. You did not say if the water pump was new or not, but your motor is from a time when some versions had serpentine belts and some had V-belts. The waterpump is different, depending on the belts used. The serpentine belt type very often runs in reverse of the V-belt type.

Also, if the serpentine belt is installed incorrectly (and still fits) then the water pump can be spinning backwards. The pulleys of the accessory items on a serpentine belt are ribbed and smooth. The ribbed pulleys ALWAYS make contact with the inside surface of hte belt, and the smooth pulleys ALWAYS make contact with the outside surface of the belt. This is always true. It should be impossible to put the right belt on wrong, or the wrong belt on right, but one might be able to put the wrong belt on wrong. This is a possibility you are facing. Check the routing of the serpintine belt.

If you replaced the water pump, and got the v-belt type, then logic says you should have had trouble putting the pulley and fan on, but this is not always the case, and you are left with a pump that looks good but the impeller vanes do not spin in the proper direction and circulation is poor at best, but possibly non-existant.

Worst case is a blown head gasket. You can have a blown head gasket that allows water and oil to mix, but still keeps the combustion gases where they belong. If this was true in your case, you should have a very heavy build up of sludge in the coolant, or water on the dipstick. Pull the dipstick while the engine is running and look for bubbles. (This is not conclusive unless there are bubbles, but it's a good check to make, and it's easy.) You can also drain the oil into a catch pan, then SLOWLY pour the oil into your Recycle Container and check the catch pan for water on the bottom. Water sinks in oil, so it will be on the bottom of whatever is holding it. With the engine running, the water will appear as droplets on the dipstick. With the engine off, the water will sink to the bottom of the pan, and not appear on the dip stick at all. If you're good, you can drain some oil into a suitable clear container, then put the drain plug back in, then let the container rest for a while and look for signs of water forming at the bottom. (Lots of bottled water companies use clear plastic bottles in the 1 gallon size that you can cut the top off of and collect a pint or so of oil into.)

On Sat, 05 Sep 2009 12:54:39 -0400, tom rearranged some electrons to say:

Straight water will boil over much quicker than a glycol mix.

Its acting like a head gasket.

read it all still reminds me of a stuck thermistat....installed backwards... spend another few bucks and change it even though its new ... Iv'e had them be bad out of the box before ...also had one where the poor guy was doing it at home but not watching his kid closely and when he got done he had this problem... his 10yr old decided to help him clean it and left a peice of a rag in the hole... at lest thats the story he gave me a couple days after I fixed it for him... john

I'm still thinking a T-stat (new are bad at times). I learned to check them by pressing it open and closed before I installed them.

Don't different T-stats have various heat ranges before they open/shut? Maybe an incorrect heat range?

OP has covered a lot of bases.

It is a head gasket leak.

I ran it around for 20 minutes, until it got almost to the end of the temp gauge, then stopped and waited until I could safely open the radiator cap.

Then I retested with that NAPA kit with the blue liquid. It turned yellow, indicating exhaust gases in the coolant.

My thanks to all of you for your help in this.

Tom

John,

Thanks for the reply.

I took the thermostat out, and the problem still happens.

Read the last post in the string just before your message.

I tried the NAPA block check>> (I posted this a few weeks ago but still haven't cured it)

Tom,

Depend>John,

Ashton, Thanks for the reply. I do intend to try that, since I think the leak is very small. I bought a bottle of K&W Nanotechnology Head Gasket & Block Repair this afternoon. They recommend finding the leaking cylinder first and disabling its injector and remove that spark plug before doing the treatment. I'll try it next Saturday & see what happens.

Looking back now, I flushed out the whole system back in February because I wasn't getting much heat. All kinds of gunk came out, brown rusty crap.Got plenty of heat after flushing, but this problem might be because I flushed out or loosened something that was plugging the gasket leak. But I have had the van for 3 years already so I can't complain. We'll see what happens

Tom