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They do run extremely rich on start.
Sometimes you'll struggle to restart from cold if it has only just run for a few seconds
P38A 4.6 V8 won't pull, sluggish, otherwise runs fine.
- Thread starter MrGorsky
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Sometimes you'll struggle to restart from cold if it has only just run for a few seconds
P38 Monkey
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Check colour of spark plugs…?
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Henry_b
Think outside, no box required.
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ideally yes long story short with a flat tappet cam the cam follower and lobe have bed in to each other at around 2-3000rpm, the reason for this is the cam follower has a crown machined in to it which allows it to spin, if the break in procedure isn't done correctly or at all, then the cam will wipe out one or more of the followers and its engine rebuild time again.
Henry_b
Think outside, no box required.
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In that case they can be ruled out, does your motor run LPG?
P38 Monkey
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Exactly so. That is definitely a Landyzone interpretation of Bertrand Russell's "Cretan liar paradox" solution of evidence analysis.You mean like having a cuppa or 2 before deciding to take a grinder to that bugger 10mm nut
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P38 Monkey
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For our information, exactly what does the cam break-in procedure involve..?? What is the actual procedure?ideally yes long story short with a flat tappet cam the cam follower and lobe have bed in to each other at around 2-3000rpm, the reason for this is the cam follower has a crown machined in to it which allows it to spin, if the break in procedure isn't done correctly or at all, then the cam will wipe out one or more of the followers and its engine rebuild time again.
Henry_b
Think outside, no box required.
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Starting the car and varying the revs from 2000-3000rpm for around 25minutes
P38 Monkey
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Thanks - presumably just after a fitting a new cam and/or followers.Starting the car and varying the revs from 2000-3000rpm for around 25minutes
Useful to know that - thank you.
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In first post you mentioned plugs & leads only couple of years old, but that doesn't mean they havent gone bad. As said above what do they look like ?
Rebuilt engine should have good compression. While the plugs are out, check that.
Is the fuel rail pressure regulator actually working ? Check the small vacuum pipe is not leaking.
Rebuilt engine should have good compression. While the plugs are out, check that.
Is the fuel rail pressure regulator actually working ? Check the small vacuum pipe is not leaking.
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This is what V8 Developments told me....
For running in we recommend 20mins breaking in on Comp cams break in oil and additive, broken up into 4 x 5min sessions. Each session keeping the rpm over 2,000 and blipping the throttle but keeping below 4,000rpm. Very important please don’t let the engine overheat.
So that's first start the car for the first time with the barnd new rebuilt engine..... and then rev it over 2000 rpm blipping the throttle for 20 minutes!! I found it pretty worrying, but like most things, once you actually do it, it's not so bad.
Someone around to check for leaks is a good idea, and I doubt it'd be a problem to cut one "session" short to correct a leak or something like that.
The squeal from the power steering bleeding itself shat me up for a bit though.
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Yes it does. But that's currenlty disconected until I can get it running well on petrol.
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I plan to get them l out and double check that when I get some time. Go back to the start with it and check all my connections again. I'll report back with my findings....
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What's disconnected on the LPG ? On mine, I connected the LPG injectors, but left them unplugged so pipes to the manifold provide a suitable seal.
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Exactly the same. All the gas connections are connected and tight. All the electronics are disconnected. I've already re-checked it all once, but if I'm taking the sparking plugs out, I'll check the LPG pipework again whilst the engine is in bits.
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I also thought it'd be worth checking the coil packs. Is there a resistance value test or something I can do to see if they're within expacted tolerances.....?
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Update from forum search: primary is 0.8 ohm, secondary is 13k ohm
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I do have another set actually, I could just swap them out. They're the originals from when it first started failing to start and misfiring ages and ages ago before compression checks and engine rebuilds. A simpler more innocent time.
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It did. Been unplumbed when engine taken out and not put back yet.
ideally yes long story short with a flat tappet cam the cam follower and lobe have bed in to each other at around 2-3000rpm, the reason for this is the cam follower has a crown machined in to it which allows it to spin, if the break in procedure isn't done correctly or at all, then the cam will wipe out one or more of the followers and its engine rebuild time again.
The bedding in procedure was followed religiously, together with appropriate fluids.
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That's what I have been wondering. I've been trying to persuade him to buy a fuel pressure guage off the Bay for weeks to rule it out.
Small vacuum pipe sounds good as well. It is rather like the response when the vacuum pipe for the advance used to fail on old carb engines using a dizzy.
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Like this one in Langley !! I have also used a tyre gauge screwed onto the schrader valve.
