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427 running issues

Bigsieuk

CCCUK Member
Just stalled my 67 as I was putting it in the garage, now it will barely runs - any ideas? Could stalling mess the gears on the distributor drive?
I'll check timing tomorrow but I'm thinking unlikely. Could I have damaged something more serious Cam drive??

Regards

John

427 manual 3x2, standard ignition.
 

Roscobbc

CCCUK Chairman
Unusual for something like this to happen - but not unknown. Pin at base of distributor shaft/drive shaft to oil pump can brake - rare but it has happened. Distributor shaft on my BB engined car didn't shear - but the end of the drive shaft to oil pump sheared last year on mine.
Sure its not a fueling issue - float needles - unusual but timing chain pumped a few teeth.
All unusual but not unheard off. A couple of years ago when starting mine - it backfired and chipped-off a tooth off the starter motor pinion......
 
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Bigsieuk

CCCUK Member
Thanks for the responses.

Got time in the garage on Sunday afternoon, started first time ran like a dream.

Vapour lock in fuel system? Overheating coil?

Anyway, glad it is up and running again.
 

oldmemberl68

CCCUK Member
Just stalled my 67 as I was putting it in the garage, now it will barely runs - any ideas? Could stalling mess the gears on the distributor drive?
I'll check timing tomorrow but I'm thinking unlikely. Could I have damaged something more serious Cam drive??

Regards

John

427 manual 3x2, standard ignition.
I have a similar fault ??? My is both end carbs are dripping fuel at idle and when you switch off the engine ? I've stripped the carbs down and found gray sludge behind the metering plates
My car is a very early 69 auto which I've had the for 32 years and this is the first time I've had this fault .
Regard
Pete
 

Bigsieuk

CCCUK Member
Pete,

All three of my carbs have been completely stripped down and cleaned thoroughly, its was shocking to see the amount of crud that had built up in the carbs. That crud might be blocking the needle valves from your floats. But as yours are dripping fuel even with the engine off I'm thinking its a fuel boiling issue.

Chris Sale sent me a great piece he'd written on the issues he had with ethanol and fuel boiling in the carbs which I have attached.

Basically the increasing amount of ethanol in fuel these days results in the fuel boiling in the float bowls on a hot engine, even when it is switched off. When it is running there is enough fuel flow and air flow to keep the carbs cool and the fuel from boiling in the bowls. But as soon as you switch the engine off the residual heat boils the fuel in the bowls causing it to leak out of the carbs.

With mine, having left it overnight, it burst into life first time. I realised that I usually lift the bonnet as soon as I stop for any time longer than it takes to put petrol in, this must usually let the heat out stopping the heat from building up.

Hope this helps. If not get back to me.

Regards,

John
 

Attachments

Roscobbc

CCCUK Chairman
Pete,

All three of my carbs have been completely stripped down and cleaned thoroughly, its was shocking to see the amount of crud that had built up in the carbs. That crud might be blocking the needle valves from your floats. But as yours are dripping fuel even with the engine off I'm thinking its a fuel boiling issue.

Chris Sale sent me a great piece he'd written on the issues he had with ethanol and fuel boiling in the carbs which I have attached.

Basically the increasing amount of ethanol in fuel these days results in the fuel boiling in the float bowls on a hot engine, even when it is switched off. When it is running there is enough fuel flow and air flow to keep the carbs cool and the fuel from boiling in the bowls. But as soon as you switch the engine off the residual heat boils the fuel in the bowls causing it to leak out of the carbs.

With mine, having left it overnight, it burst into life first time. I realised that I usually lift the bonnet as soon as I stop for any time longer than it takes to put petrol in, this must usually let the heat out stopping the heat from building up.

Hope this helps. If not get back to me.

Regards,

John
Problem with a carb'd V8 is that the carb;s are in the wrong position to prevent percolation. As has been said - when engine is running (and this should apply to big block Vettes) fuel pump has a return flow - so always circulating fuel and helping to keep it cool. Stop the engine and as heat will always rise - it rises through the inlet manifolds and carbs - creating the vaporisation you are experiencing. And that is also the reason in many cases for next days easy starting - excess fuel in inlet tract hasn't yet vaporised. Holley (it may only be generic gaskets) the blue re-usable ones in my experience tend to break-up in time creating particles that jam float needles - gray sludge? ethanol disolving crap in tank?
 

oldmemberl68

CCCUK Member
Thanks for your help and advice I've seen some insulating blocks /plates on the web or maybe ill make an aluminium plate/ sheild under the carbs im just in the process of cleaning out the carbs with new rebuild kits . Then ill look into a cooling method ?
Cheers
 

Roscobbc

CCCUK Chairman
I'm guessing that your tri-carb (like my L36 with single quad) has (or had) a cartridge fuel filter - one inlet from fuel pump, one main feed to carb and a smaller diameter return feed back to the tank. Even nudging 600 bhp with stroker engine and headers percolation is not a major issue with this set up - although I notice the squirters drip fuel when the engine has been turned-off - nothing too major though. The odd thing was the metal canister fuel filter. Despite the engine performance (and a 950 cfm double pumper Holley) a standard spec fuel pump (installed some 15 years ago) was perfectly adequate to fuel the engine. It was running Kop Hill that created the problem - accelerating hard up the hill and the car suffered major fuel starvation. I replaced the fuel pump with a high volume pump expecting that to resolve the issue - it didn't - and embarrassing few minutes thrashing a 911 led to another major fuel starvation issue. The canister fuel filter was the problem - I always flushed it out from the opposite direction to the flow - for many years this was adequate - this time I blew through it and the restriction was significant - it was partly blocked (and the reason for the starvation) - the OEM replacement for a '68 Vette is a super rare part now and a stupid price. A $5 canister filter for a mid 80's Jeep from the guys at Customville had the answer - and no fuel starvation for another year or so. Thing is that the Jeep filter is one presumably designed for an injected engine and probably has a much finer filter element - and yes sediment etc from the tank blocked it again - was never an issue in the pre ethanol additive days.........
Phenolic spacers under the carb or even a 'sandwich' of thinner spacers and ally plates can made a difference - but the heat will eventually get through any insulation - usually when the engine stops running. You may have issues closing the hood. You could look at the routing of the fuel feed pipe - if too close to a heat source wrap it with some Reflectix or similar insulation material - it may help.
 
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oldmemberl68

CCCUK Member
I'm guessing that your tri-carb (like my L36 with single quad) has (or had) a cartridge fuel filter - one inlet from fuel pump, one main feed to carb and a smaller diameter return feed back to the tank. Even nudging 600 bhp with stroker engine and headers percolation is not a major issue with this set up - although I notice the squirters drip fuel when the engine has been turned-off - nothing too major though. The odd thing was the metal canister fuel filter. Despite the engine performance (and a 950 cfm double pumper Holley) a standard spec fuel pump (installed some 15 years ago) was perfectly adequate to fuel the engine. It was running Kop Hill that created the problem - accelerating hard up the hill and the car suffered major fuel starvation. I replaced the fuel pump with a high volume pump expecting that to resolve the issue - it didn't - and embarrassing few minutes thrashing a 911 led to another major fuel starvation issue. The canister fuel filter was the problem - I always flushed it out from the opposite direction to the flow - for many years this was adequate - this time I blew through it and the restriction was significant - it was partly blocked (and the reason for the starvation) - the OEM replacement for a '68 Vette is a super rare part now and a stupid price. A $5 canister filter for a mid 80's Jeep from the guys at Customville had the answer - and no fuel starvation for another year or so. Thing is that the Jeep filter is one presumably designed for an injected engine and probably has a much finer filter element - and yes sediment etc from the tank blocked it again - was never an issue in the pre ethanol additive days.........
Phenolic spacers under the carb or even a 'sandwich' of thinner spacers and ally plates can made a difference - but the heat will eventually get through any insulation - usually when the engine stops running. You may have issues closing the hood. You could look at the routing of the fuel feed pipe - if too close to a heat source wrap it with some Reflectix or similar insulation material - it may help.
Cheers
The fuel lines have been rapped as surgested. The fuel seems to weep from the holes just above the butterflys evens after running the engine for a 15/20 minutes and wilĺ empty the flue bowls when i use the car i normaly drive with the bonnet slightly left open i dont have an inline filter ? Only the bronze ones in the carb inlet pipes and there are clean as a whistle i only had gray sludge in the end two carbs the center one was fine just waiting on rebuild kits to try again
 
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