V8 rebuilt no spark

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ricey30
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Re: V8 rebuilt no spark

Post by ricey30 »

Hi all

Quick update

New comp tester gave the following results

Right bank dry test full throttle 90ish per cylinder on all cylinders

Left bank dry test full throttle 90/100 per cylinder on all cylinders.
Left bank wet test on one cylinder went up to 120
Left bank with rocket oededtsl shims removed compression completely lost.

All tests on newly honed bores new rings and freezing cold engine and outside temp at 2celcius.

Do you all think it can be conclude that whilst not great 90/100 is enough for the engine to start??



(In the meantime new plugs to go in tomorrow and see if it will start.)



DaveEFI
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Re: V8 rebuilt no spark

Post by DaveEFI »

Yes. Compression testing on a newly built engine cold would tell you if you'd forgotten to fit a piston, but not much else. :D
Hydraulic tappets can take some running time to adjust themselves fully too.
And trying to start a new engine with a carb which isn't correct for the engine is less than ideal too. Too many variables.
Dave
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ricey30
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Re: V8 rebuilt no spark

Post by ricey30 »

Dave your right if it doesn’t fire with the new plugs I have s 1404 off a 3.9 which I know o be good in my mates garage I will borrow that and that will eliminate carbonation at least to get it started

Thanks for support

ricey30
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Re: V8 rebuilt no spark

Post by ricey30 »

No further forward

Swapped carb and brand new plugs

Sounds like it’s trying to catch
Got a small back fire from exhaust
Lots of fuel vapour from crankcase breather

Battery gave up so oncharge pending setting fire to out in the morning 😕

If anyone can rccommehd a Mobike mech who knows v8 I’m happy to chuck money at him to point out where I’m a muppet I’d be grateful

Thanks Phil

scudderfish
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Re: V8 rebuilt no spark

Post by scudderfish »

Have you absolutely, positively, definitely checked you've got the right order on the plugs? It's an easy thing to overlook or assume is right, but only takes a couple of mins to check. If/when you do, assume it is wrong until you prove otherwise. I don't want to insult your intelligence, I just know the number of times I've gone looking for an esoteric problem when the solution was something simple and obvious in hindsight.

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ChrisJC
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Re: V8 rebuilt no spark

Post by ChrisJC »

Is there any way you can tow-start the car?

Chris.
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Series IIA 4.6 V8
R/R P38 4.6 V8
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