Engine will not accelerate

[marc silva]

Just started my new engine. Started on the 4th revolution and idled perfectly! However, when I go out on the road it will not accelerate. It drives around the neighborhood o k up to about 15 mph but when you give it more gas it does nothing but suck air. The carb has been non operational for 6 months. I will take it apart and clean it in the morning. Hopefully that will correct the issue. I can't imagine that this California gas could plug anything up because it is like acetone. It evaporates before it hits the ground. Any Ideas?

Thanks, Marc

[700rpm]

It could be a result of poor gas, either sitting too long in the carb or in the tank. But it might also be a bad condenser, which can cause a similar problem. Or your points could need cleaning and setting. Be assured it is something pretty simple, if your engine is brand new.

[Mitch//pa]

Ethanol has a short shelf life
The model A gas tank is very easy to drain
Let's hope the fuel fed into your new engine is not the issue.. It can stick valves, rings and plug up a carburetor..
If the fuel is yellow it's bad, it also has a strong stale smell to it.. Good fuel is clear
What Ray said basics

[marc silva]

I just removed the complete intake and carb and popped out the distributor and re installed it and adjusted timing and point gap. New plugs and gas and there you go. It should have worked no problem but didn't.

[Tom Wesenberg]

Make sure rodents haven't plugged up your exhaust.

Make sure the points arm has good spring tension.

My first thought was the crap gas has plugged up the carb, or caused sticky valves.

[Marshall V. Daut]

Sponsored Links (Register now to hide all advertisements)

A Model "A" engine that won't accelerate much above idle often has a clogged muffler, along the lines of what Tom Wesenberg suggests. Enough exhaust can flow to keep the engine idling and under low power demands (up to about 15mph), but anything more than that and the exhaust backs up into the engine = no acceleration. In the interim while you were waiting for your new engine, rodents may have nested in the muffler, or possibly an internal baffle has come unwelded and is blocking air flow.
Test: It will be noisy, but drop the muffler pipe from the exhaust manifold in your garage and try accelerating. If it accelerates smoothly and wants to "go", your muffler is clogged.
Marshall

[Larry Jenkins]

Originally Posted by Marshall V. Daut

A Model "A" engine that won't accelerate much above idle often has a clogged muffler, along the lines of what Tom Wesenberg suggests. Enough exhaust can flow to keep the engine idling and under low power demands (up to about 15mph), but anything more than that and the exhaust backs up into the engine = no acceleration. In the interim while you were waiting for your new engine, rodents may have nested in the muffler, or possibly an internal baffle has come unwelded and is blocking air flow.
Test: It will be noisy, but drop the muffler pipe from the exhaust manifold in your garage and try accelerating. If it accelerates smoothly and wants to "go", your muffler is clogged.
Marshall

And I remember the article you wrote about this in the Model A Trader. A very good read..

I still have my copy.

Larry

[Marshall V. Daut]

Thanks, Larry. That was a fun column to write for the printed magazine "Model A' Trader". Hopefully my "What's Wrong With It NOW???" articles helped some Model A owners repair weird problems with their cars. That plugged muffler problem has surfaced in my life in a couple cases since then, as older cheapie Midas mufflers self-destruct internally. I think we'll see more and more postings like this one in the future - assuming a plugged muffler is actually the original poster's problem. TBD...
Marshall

[Steve Plucker]

So what happened to the "Model A Trader"?

Pluck

[Larry Jenkins]

Originally Posted by Steve Plucker

So what happened to the "Model A Trader"?

Pluck

Back when Marshall and I were writing articles for the Model A Trader, it was owned and published by John Yeagle. I see there's a site shown if you do a search "Model A Trader."

Not too big, and no mention of John.. Anything to add, Marshall?

Larry

[Marshall V. Daut]

Nope. Nothing new to report. I received a mass mailing notification in the early 2000's that John was suspending his printed version of "Model A Trader", but would continue with an electronic one. That was the last I heard from him. There were still a couple of my columns in the pipe for publication that apparently never appeared in print. I have checked every so often over the years since to see if it was still a going operation, but 'didn't see much activity. The fact that NO ONE on the two major Model A message boards has mentioned "Model A Trader" in the past decade or so tells me it's probably defunct. Too bad. Lots of good articles and advice in those pages, including testing new Model A products that were coming onto the market back then. It was a forerunner of John LaVoy's "Model A Times" in that regard.
Marshall

[Marshall V. Daut]

I just did a Google search and apparently "Model A Trader" is still active, electronically at least. I'm glad I kept my back issues when it was still being printed. I have some early "Model A Times" issues, but I need to make a mass back issue order from John LaVoy while he still has them on hand. Once they're gone, they're gone.
Too bad today's recent converts to the Model A world don't have access to the original "Model A Trader" issues from the 1990's-early 2000's. John Yeagle put out a high quality printed magazine. I think it just became too much work for him compared to the number of subscribers. Most of the Model A people on-line back then were grizzled old veterans with years of experience working on these cars. Not many felt the need to scubscribe to a magazine like that, I guess. But with a whole new crop of Model A people these days just learning about the cars (as can be gleaned from the type of recent posts), I would think a printed "Model A Trader" might have a wider base of support now. However, with John's LaVoy's "Model A Times" doing so well, that might be too much of the same thing to be a success. 'Dunno. I only know that I still bemoan "Model A Trader's" printed format demise. I hope all is going well for John Yeagle.
Marshall

[rocket1]

It could also be a bad coil,i had that problem on my early olds,when i reved it up the engine would start to die,i thought it was the fuel pump,the last thing i replaced was the bad coil.

[goodoldvic]

Check your gas cap vent also, good luck

[Gary WA]

Originally Posted by marc silva

Just started my new engine. Started on the 4th revolution and idled perfectly! However, when I go out on the road it will not accelerate. It drives around the neighborhood o k up to about 15 mph but when you give it more gas it does nothing but suck air. The carb has been non operational for 6 months. I will take it apart and clean it in the morning. Hopefully that will correct the issue. I can't imagine that this California gas could plug anything up because it is like acetone. It evaporates before it hits the ground. Any Ideas?

Thanks, Marc

Try this:Site Index (Model-A.org) Thanks to the supplier of article.

[marc silva]

I got the issue resolved. I re set the timing and presto it runs like a champ! Just goes to show that even when you think you have it mastered and are paying attention like so many times before (so you think) you can still screw up! ALWAYS double check your work!! Even though you know that you are good........

I have a hard head!! I learn the hard way no matter how many times it takes, but when I am done I really know it!!

[tbirdtbird]

For some reason timing is the Achilles heel of so many.......