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Alan,
I used exhaust heat wrap snadwiched between two layers of aluminum for a heat shield on my MGB and it helped dramatically. I suspect your lean condition is the cause of a lot of your heat problems.
If you have the time, drop the distributor in the mail. I have absolutley NO problem with checking it over again. If the car was THAT lean, the new distributor curve would probably make it SO lean that it won't even run!

If you get the car back on a dyno, next time get the printout with fuel mixture, from idle all the way up to redline! It shouldn't have been run on the dyno before checking the mixture! That's a recipe for disaster!
 
Thanks Jeff, but I suspect the distributor is fine. He told me that he couldn't get it to hold an idle below 2k. I have a feeling that it being so lean might have contributed. As soon as I get an adjusting tool and a vacuum gauge I'll have a go at fattening up the delivery...

I'm going to give the distributor a try as soon as I get the other two problems sorted - I've leaked so much oil its off the dipstick. I got underneath before, and it now looks like its coming from the filter area rather than the back of the engine plate, but there is so much of it it is hard to tell - it has coated the entire bottom of the gearbox, which is why it looked like the box was leaking too from the side. Oh and it only leaks when the engine is running. SWMBO is not very happy with the state of the garage floor to say the least...

If the distributor is still troublesome after I try it out, then I'll send it back. I'll give you a call before I do if thats the case.
 
Alan, make sure your mechanic installed the bronze washer on the top bolt of the rear main seal housing. I dont know why but the manual(s) say it will leak without the special washer.
 
ALAN- aLSO REMEMBER THAT SOME OF THE SPIN ON OIL FILTERS WERE SOLD WITH FAULTY WASHERS.
DON
opps!Thats what happens if you have to look at the keyboard when you type,.
 
I think (or hope) the leak is coming from around the sandwich plate or the spin on filter. I need to buy oil before I can fire it up again to see where exactly. Its the only explanation given the amount of oil that is coming out. Its covered the whole of the bottom of the gearbox - which is why I thought it was leaking from the back. It dripped on to the exhaust back there and started smoking.

I hope its that simple.
 
I think the guys who mentioned the lean condition are right on. When we were working on the 250 the back carb was back firing and we could not get it to run right. The carbs were too hot to touch. We went through the set-up procedure 3 times without good results. Finally we richened the rear carb and were able to get a decent idle. Howerer the engine had no power above 4000. Steve eventually discovered that his intake manifold was warped. After having it machined flat everything was fine. That's not to say that your manifold is warped, just that the heat and hot carbs are a symptom of lean mixture.
Have you run it on the road enough to see the color of the inside of the tail pipe change? It should be light tan. If it's closer to white it is running lean.
You commented last week about running out of gas when you thought there was 1/4 of a tank. Remember to check the voltage stabilizer. The temp gauge will read about 1/4 high if the stabilizer is faulty. The gauges are designed to work at 10 volts. If the stabilizer is bad they will see 10 to maybe 14 depending on the output of the charging system.
You do need to address the temperature ASAP. TR6 heads have very little space between inlet and exhaust valves. Too much heat can crack that small area between the seats. I had it happen on my '71.
One last thing... If you are not comfortable or experienced with the adjustments on Stromberg carburetors PM me. I will be glad to write down the steps and or talk to you on the phone.
Bob
 
Just a thought and I'm sure that you've already checked it, but make sure that the timing is not retarded. That can cause similar problems with the heat and if in conjunction with lean mixture, would only make it worse
 
Its in a shop having the oil leak looked at. Until that gets fixed I'm loathe to try to run it for any time - SWMBO is well unhappy at the state of the garage floor right now, and I don't want to add any more flammables.

I borrowed the stuff needed for tuning off a friend (I also ordered it from Moss so I'll have a set). I did the old RTM thing - there is a letter missing from the way I usually write that so it might not scan. I'll have a try at getting it to run when it comes back. From what I read it doesn't seem too hard, just tedious and time consuming. But then I'm sitting here with nothing better to do right now - took the day off to go for a drive and can't. If I can get it running ok, maybe I'll get to try the new distributor I have today too...

/ubbthreads/images/graemlins/cheers.gif
 
Two words for the condition of the floor in your garage. Kitty Litter. Or, Oil Dry, available at most every parts store.
 
Use mineral spirits. You can pour it on the oil spots, work it in with a broom if you want, then let it evaporate. The mineral spirits will disolve the oil and carry it away during evaporation.
This works for oil right after you spill it as well as oil that has soaked in a little. I don't know if it will work on oil that has been there for a long time.
 
I hope so - there is even more oil down there now. I'm thinking of locking the door to the garage for a few days.
 
Checking voltage stabiliser

The one behind the speedo you mean right?
Output sb 10V?
Sorry I'm being dim, but don't want to go fiddling behind the dash unless I have to.
 
Re: Checking voltage stabiliser

Another out of the blue post!
 
Re: Checking voltage stabiliser

Perhaps if you look at what the post is a reply to - the response about a dodgy stabiliser causing the tank to read high.
 
Re: Checking voltage stabiliser

Alan,
Yes it's behind the speedo. In my recent case a PO left it hanging on the wires. We ran dry in Bakersfield CA. Judging by the neighborhood and the looks from the passing cars we were fortunate that it was early morning. Had it been after dark we would have been ground up and served in Tacos. The stabilizer uses the speedo mounting post as a ground. Once I put it back on the post it worked fine. Years ago I had one completely fail leaving me stranded on the left shoulder of the DC Beltway thinking I still had 1/4 of a tank. It was easy to replace. There are postings possibly here or on other Inet sites with instructions for building a solid state device to replace the quaint OEM piece. Let me know if this helps.
Bob
 
Still need help

So with the oil leak fixed I go on to try to fix the overheating problem. I've had a few people suggest that I check timing, so I do.

It was running 4 deg advanced instead of 12 deg retarded...

Worse yet, the distributor thats in it won't stay retarded. Every time I adjust and clamp it down it goes back to 4 deg advanced. Fortunately I have my rebuilt distributor - the one I was told was bad by the mechanic. I swap them out and it goes in and sits at the correct value. Rock steady no bother.

This exposes the second problem. The one I still need some advice on. I know why the mechanic was complaining about the distributor. The carbs won't balance. The middle and front ones are misbehaving. When you try to synch the airflows they start to run away - the car sits at 3000 rpm, even with the fast idle screws backed all the way out on the others. It is extremely sensitive too - 1/2 a turn is all it takes to induce this.

The carbs are clearly bad in some way (although I'm told rebuilt of course). I had a friend over last night whose a lot more expert than I am - but then if he could spell carb that would qualify him here - and he's stumped as to why this is happening. We checked the obvious stuff.

Can anyone offer an explanation as to why this is happening, and better yet how to fix it. I'd prefer not to waste a week sending them off to get rebuilt again (but correctly this time) if it is a simple fix.

TIA once again.
Alan
 
Re: Still need help

This is a SWAG, but have you checked to see if the temp. compensaters on the carbs are sealed properly? I remember someone who had a similar problem years ago ands traced it to a air leak in the compensaters.
 
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