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Ben Nichols
confused24.gif

Hi All

Me again..........

So, was taking the car to have the carbs set up this morning, got about a mile and a half and it stopped. Started popping and then one final pop/fart noise and it died.

The AA (recovery guys in the UK) came and found no spark. He thought the distributor had failed - removed it and it seemed fine. Then he thought maybe the distributor drive gear - we removed that and it seems fine, the gears are good, it seats properly. We did get a spark but not a reliable one.

He thinks it could be the drive gear on the crankshaft that has failed and the lack of drive is causing the problem to the drive gear and on to the distributor........

My questions I guess are:

1. Is this likely/possible? Would it just fail with no warning?
2. How is it possible to check, or isn't it?
3. It sounds like a full strip down again.......tell me its not although I am pretty sure it is
4. Any other explanation for the fault.........?

Any help appreciated - I was planning on taking the car to Le Mans in 3 weeks which looks unlikely......

Thanks

Ben
wndsrfr
Be careful to see that the points are operating properly in the distributor I've seen the phenolic rub bar worn down and not operating properly at all...
Ben Nichols
QUOTE(wndsrfr @ May 27 2019, 12:48 PM) *

Be careful to see that the points are operating properly in the distributor I've seen the phenolic rub bar worn down and not operating properly at all...


The AA man said they were fine, its really confusing as it had been running fine and was rebuilt only last year, only done about 400 miles since
TheCabinetmaker
Condenser! Won't run if it's fried. Btw, is a recovery guy a tow truck driver? If so, he doesn't know crap about your 914
Superhawk996
Time to work the basics.

Only 3 reasons an engine won't run:
No Spark - easy to check.
No Fuel - easy to provide via starting fluid
No compression easy to check with compression gauge.

Everything else on the engine is function of providing the 3 things above in the proper sequence.

Work though the basics in the order listed. Popping & backfiring noises are a result of spark coming at the wrong time (i.e. timing & dwell) or wrong fuel mixture.

Guessing doesn't work. Get a shop manual - doesn't have to be factory manual. Haynes is fine.

Tdskip
Agree that sounds electrical, and condenser is a good place to start.

The AA guys in the UK are actually much more mechanically aware than what we see in the US, not uncommon for them to fix roadside issues actually.
barefoot
QUOTE(Ben Nichols @ May 27 2019, 07:43 AM) *

confused24.gif

Hi All

Me again..........

So, was taking the car to have the carbs set up this morning, got about a mile and a half and it stopped. Started popping and then one final pop/fart noise and it died.

The AA (recovery guys in the UK) came and found no spark. He thought the distributor had failed - removed it and it seemed fine. Then he thought maybe the distributor drive gear - we removed that and it seems fine, the gears are good, it seats properly. We did get a spark but not a reliable one.

He thinks it could be the drive gear on the crankshaft that has failed and the lack of drive is causing the problem to the drive gear and on to the distributor........

My questions I guess are:

1. Is this likely/possible? Would it just fail with no warning?
2. How is it possible to check, or isn't it?
3. It sounds like a full strip down again.......tell me its not although I am pretty sure it is
4. Any other explanation for the fault.........?

Any help appreciated - I was planning on taking the car to Le Mans in 3 weeks which looks unlikely......

Thanks

Ben

If it ran this morning the drive gears did not wear out in a short trip, not a mechanical issue. The crank drive gear is very robust. did you run out of fuel, or fuel pump stop running ??
Check the point dwell and condenser

worn
QUOTE(Tdskip @ May 27 2019, 05:09 AM) *

Agree that sounds electrical, and condenser is a good place to start.

The AA guys in the UK are actually much more mechanically aware than what we see in the US, not uncommon for them to fix roadside issues actually.

Also, now that you have pulled both distributor and the drive gear the timing is probably off. That can keep the car from running, although you should still have some spark. Do you have a timing light?
Ben Nichols
Thanks for the help guys.

I have admitted defeat and found a specialist who now has the car and will hopefully sort it one way or the other......

Ben
Tdskip
QUOTE(Ben Nichols @ May 30 2019, 12:54 AM) *

Thanks for the help guys.

I have admitted defeat and found a specialist who now has the car and will hopefully sort it one way or the other......

Ben


There is absolutely nothing wrong in knowing when it’s time to call in a professional. Please let us know what ended up being the problem and here is to a fast return of the car to you so you can get some driving in.
Ben Nichols
QUOTE(Tdskip @ May 30 2019, 02:16 PM) *

QUOTE(Ben Nichols @ May 30 2019, 12:54 AM) *

Thanks for the help guys.

I have admitted defeat and found a specialist who now has the car and will hopefully sort it one way or the other......

Ben


There is absolutely nothing wrong in knowing when it’s time to call in a professional. Please let us know what ended up being the problem and here is to a fast return of the car to you so you can get some driving in.


Well, so an update. Basically it seems the cam is worn out which means the valves cant be adjusted properly, meaning it's never run right and it giving up was the final straw. The carbs couldn't be set up properly and it was impossible to tune.

Anyway it's now at a proper engine builders in the uk (they build lots of race and fast road engines, called GAC if anyone has heard of them) having a new cam and followers and a full going over, should be ready in about 8 weeks with about 130hp. I dont want anymore, just for it to be reliable and not too complex.

I'll let you all know when it's done

Ben
mepstein
QUOTE(Ben Nichols @ Jul 15 2019, 02:50 PM) *

QUOTE(Tdskip @ May 30 2019, 02:16 PM) *

QUOTE(Ben Nichols @ May 30 2019, 12:54 AM) *

Thanks for the help guys.

I have admitted defeat and found a specialist who now has the car and will hopefully sort it one way or the other......

Ben


There is absolutely nothing wrong in knowing when it’s time to call in a professional. Please let us know what ended up being the problem and here is to a fast return of the car to you so you can get some driving in.


Well, so an update. Basically it seems the cam is worn out which means the valves cant be adjusted properly, meaning it's never run right and it giving up was the final straw. The carbs couldn't be set up properly and it was impossible to tune.

Anyway it's now at a proper engine builders in the uk (they build lots of race and fast road engines, called GAC if anyone has heard of them) having a new cam and followers and a full going over, should be ready in about 8 weeks with about 130hp. I dont want anymore, just for it to be reliable and not too complex.

I'll let you all know when it's done

Ben


beerchug.gif
Cairo94507
Keep us updated with pics so we can enjoy it with you. beerchug.gif
burton73
Hi Ben,

We have AA - Auto Atlanta Dr. 914 George, and AAA Automobile Club roadside repair and AA alcoholics anonymous 12 steps programs. Some of our members could use a 12-step program for buying to many cars or parts to the point where it may be a problem.

Cheers to you my 914 Brother

Bob B
beerchug.gif
Ben Nichols
Here is a link to a magazine feature of the guys doing the work...proper old skool engineers, amazing what they do

https://magazine.heritagepartscentre.com/en...ower-and-glory/

Hope the link works
porschetub
Same in my country the AA guys are usually highly trained mechanics,generally guys that have a lot of experience,the AA roadside service is a lot smaller and has less guys on the road due to cars being more reliable these days.
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