Autolite Spark Users Only
 

My 36 runs very rich, carb has been replaced and adjusted more than once. Current plugs are Autolite 388 and by what I have read that is a pretty hot plug. Plugs are black as well as the tail pipe, no smoke. I see a lot of people use the 216 or 386. Should I stick with what I have or try something else? What do you use "Autolite users only please" not to confuse the matter.

Re: Autolite Spark Users Only
 

I use Autolite 216 in my 8BA 276" engine with a Rochester 2G carb. My plugs show a medium brown color. I'm unsure how much effect the rest of the ignition system has on the plug color. Dirty points and plug wires with high resistance could affect plugs.

Re: Autolite Spark Users Only
 

I run 386's on the Early engines with the 18MM thread size with ZERO issues. On a stock engine, a 388 Autolite should perform fine as well although it is supposedly a heat ranger hotter than should be run... or so I'm told

Also, in recent years I only run autolites of NGK

Re: Autolite Spark Users Only
 

what carb do you have on your 36? Stromberg or Ford 94 type? I use and recommend auto lite 216. power valve can be leaking in a 94 and cause this problem

Re: Autolite Spark Users Only
 

I don't know I just bought the car and I'm trying to figure out all these things out is it on the carburetor itself? Also I like to determine the engine model which has been replaced.

Re: Autolite Spark Users Only
 

There is an article on ID engines, I'll have to try and find it. Evolution of the Flathead is a good article, but my copy is like 3.4 Mb and too large to load.

Re: Autolite Spark Users Only
 

216’s are too small (14mm) for the early 18mm heads 386 is the 18mm equivalent

Re: Autolite Spark Users Only
 

Don't understand why you are trying to correct a richness problem by changing spark plugs.
To me the most obvious thing to do is to address carburetor jetting, etc.
And it could be something as simple as a clogged air cleaner.

Re: Autolite Spark Users Only
 

I'm sure that will be a discussion for a later date, I have many things to sort out before I address that. I was just curious what others were using for plugs, I didn't read many using the 388.

Re: Autolite Spark Users Only
 

alanwoodieman,

I'm not sure what carb this is, I can't find any markings on it.

Re: Autolite Spark Users Only
 

Stromberg carb, so I would think too large jets, back up and take a picture of the engine head. take the air cleaner off and make sure it is not clogged up, It appears to be a dry type and the "cleaner" part of the air cleaner is a wrapped up bunch of fiber mesh just under the top cover ,remove wing nut and take it off and then remove this and see if the richness goes away

Re: Autolite Spark Users Only
 

If no marking, possibly an aftermarket Stromberg 97

Re: Autolite Spark Users Only
 

The Model 40 Strombergs had no markings... But his is a Chinese knockoff of a stromberg,.

Re: Autolite Spark Users Only
 

IMO you need to pull the carb and send it to one of the rebuilders here on the Barn and have it checked out/setup. Running a engine with a very rich mixture and lead to premature ware on the cylinder walls and rings. A carb fix is way cheaper and easier than a rebuild. The early repo carbs have known fuel leakage issues. In fact, it is my understanding that the really early ones can not be repaired (for a reasonable price) and you are better off with a new/rebuilt one.

Re: Autolite Spark Users Only
 

Although rebuilding is a good idea (if needed), that is not going to resolve any jetting issues which may be the only problem.

Re: Autolite Spark Users Only
 

Here is a pic of rich on my Autolite 388 plugs, one doesn't look too bad.

Re: Autolite Spark Users Only
 

Wait, wait! Did these two plugs come out of the same engine at the same time? If so, the problem is not the carb.

Re: Autolite Spark Users Only
 

Before you can make a blanket statement like that, don't we have to know what cylinders they came out of? If they came out of cylinders serviced by the same side of the carburetor, you are probably right, but if they are serviced by different sides, it is possible that one side (barrel) of the carburetor may be functioning properly and the other side is not.

Re: Autolite Spark Users Only
 

I did not keep track of there position I will get new plugs after I deal with some other issues and monitor more closely. I agree that one is worse than the other. I will check to see I have three others that are really black.

Re: Autolite Spark Users Only
 

Only one real black one out of the 8