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Spitfire overheating spitfire!!!!

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jbarry

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!@#$%^&!@!@!!!

I'm not sure what the deal with this is...
it's a 1980 spitfire,

it overheats... even though I installed a brand new radiator, all new hoses, electric fan, and have flushed the system several times with that Prestone radiator flush stuff... also has a new thermostat... only thing not replaced is the water pump, but I took it out and it looks new (no wobblies,no corrosion, and turns smoothly).
Any ideas?
(the previous owner was running it without a t-stat)

Any help would be appreciated...

here'e something else to consider... It also has carb issues....(it dies after the engine heats up) is there any way these 2 probs could be related???
 
Could you be more specific about the overheating?

Have someone do a quick chemical test for combustion byproducts in the coolant. I know you wouldn't like the results if it turns out positive, but better to rule out this possibility from the start. A combustion leak puts more heat into the cooling system than any radiator can handle.
D
 
Dave;I know your problem i've had the same problem before i installed the factory heatshield,after i installed it it all went away.Your carb is vapor locking/percolating.Sometimes you'll find them on Ebay around $35.00.I have a 1980 Spitfire 1500,Your car is fine just needs that heatshield,its an easy bolt on. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/savewave.gif /ubbthreads/images/graemlins/patriot.gif
 
Another possibitity is that some one may have installed an incorrect water pump. Make sure the pulley is the proper diameter. Pumping the water too quickly won't take away enough heat. T.T.
 
The wrong pump will have the water moving to SLOWLY. There are two diameters of pulleys on these pumps. The engines in the spit need the pump with the smaller diameter (about the size of the pump) The other pump has a larger diameter pulley and will turn to slowly, overheating at slow speeds.
 
Are you sure it is overheating? If you are relying on the temp gauge, make sure that it is actually correct. Ie a defective voltage regulator can also raise the temp reading. An infrared thermometer is a good double check. (how about the gas gauge does it seem to be accurate?)
Next get a if you also have carb issues, you may need to start with a good tune up to make sure everything is really set correctly. Remember that lots of "carb" problems are ignition problems. Bad timing will also make the engine work much harder than normal and generate far more heat than it should.
Also when does the overheating occur? stop lights, highway ????
Yisrael
 
What were the results of your chemical flush? Did you get a lot of rust coming out? If so, a clogged journal can do wonders at overheating an engine. Chemical flushes will clean the light stuff, but won't touch the hardened blockages.
 
timing checks out.... it is at 1 degree ATDC...
when I flushed it... it had lots of rust...
the faactory heat shield is in place, and the bottom of the carb is relatively cool to the touch...
the temp gauge shows between 3/4 of the way up, and all the way up (if that makes sense)... I don't get it out on the road, so this is idling in the driveway(ok, well, not "idling"... it "idles right now @ approx 1500 rpm) and the outside temp is 70 degrees... the coolant overflow bottle begins to squirt coolant up about 2 or 3 feet into the air after 15-20 minutes of run time.

as far as other engine stuff goes, it has a new head gasket, timing belt... new exhaust/intake manifold gasket(basically all new gaskets/seals except the rear main seal) new coil, pertronics, plugs, wires, cap, rotor... valves recently adjusted to factory specs...hmmm- that's about it... oh wait- it has new tires too! /ubbthreads/images/graemlins/grin.gif
 
[ QUOTE ]
What were the results of your chemical flush? Did you get a lot of rust coming out? If so, a clogged journal can do wonders at overheating an engine. Chemical flushes will clean the light stuff, but won't touch the hardened blockages.

[/ QUOTE ]
How can I tell if there are hardened blockages? and is it possible to clean them out?
 
Does a spitfire have a block drain? If so you can sometimes clean em out - mine was blocked up on a 2L TR3 motor and I pulled the block drain and nothing came out. After gently poking a stiff piece of baling wire up in there and chipping away for about 30 minutes it broke free and I was able to flush a good deal of crud out that wouldn't come out through the normal methods of flushing. It has been running much cooler since.

With no block drain you're in for more work (and even with a drain I got lucky).

The "right" way is obviously to pull the engine, strip it, and get it boiled, dipped, or whatever.

I think it was Bob Shaller in "More BS about TR's" that recommended the flush you did followed by a 30 min. run with just water and a box of baking soda and then another chemical flush. Don't know if it's voodoo or not but what do you have to lose?
 
James,
I posted a detailed reply to your carburetor problem last night. Did you have a chance to read it?
I think your overheating problem is, in part, the result of your carburetion problems.
I've asked a number of the same questions you are being asked here, in last night's post as well as earlier posts. If the carb problems are resolved let us know.
IMHO Starting a new thread for the same problems you mentioned in the earlier thread is not the way to get yur car running.
I apologize for being harsh, but that's the way I feel.
 
James -

I know you are frustrated, especially with the weather getting to be top down weather. But I'm with Bob on this one - I think the main problem with more than one thread is you'll get a bunch of different opinions and ideas on different stated problems, and you won't be able to systematically work your way through this. Based on your other thread, I think you still have a carb problem. Based on this thread, you may have other troubles too, but how about we fix that carb problem first?

So let me stray from this thread. I don't think it is the needle valve which controls gas into the float bowl. If it were stuck open you would see gas gushing out of the bowl vent because the pump would never stop pumping gas (spoken from very recent experience).

Now, on to your short needle problem (boy someone could really have fun with that line!) I think you need to look at that harder. The explanation that the air valve would just ride lower doesn't jive with my experience. I think the air valve bottoms out on its own machined seat in the carb - it does not bottom out by wedging the needle in the seat. So if you have too short a needle, the air valve is still bottoming where it used to, but now you are drawing gas in because the needle is too short. Or you may have a misalgned needle and you are not getting it low enough in the jet. I may be shot down by those more experienced with ZS carb construction, but I just looked at my TR4 carb, and that is the way it works.

That's all I got for now, hope it helps. Good luck and please let us know your progress.

Randy.
 
Dave you also may want to consider the air-intake-cowl that British Leyland installed in the late model slanted radiator Spitfires it bolts to the lower (5 bolt hole)spoiler & directs the flow of air up-into the radiator better.Its a part number PN;WKC4224 They are not available in the catalogs.And available here on this website.They do work I have one on my 80 Spit. Ken /ubbthreads/images/graemlins/savewave.gif /ubbthreads/images/graemlins/grouphug.gif /ubbthreads/images/graemlins/cheers.gif
 
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