New Project begins, 1974 P6 3500 V8

Hi All, many thanks for all the input, much appreciated :), So new SD1 clutch plate ordered from MBGD parts, much better quality then the one I fitted in 2019 when I did the conversion, anyway I thought I had checked the movement of the old plate on the input shaft splines but I had used my spare shaft , so naively thinking all was good, then Stu said "Have you tried it on the actual box splines or just your old input shaft, wasn't sure by what you said. " Ahh so checked the old plate on the g/box splines & could only just get it on, no back & forth movement....so that'll be it then & explains why it was so hard to get the engine to fit flush against the bellhousing last month. Also the g/box input shaft splines had got dusty/dirty from my engine bay clean up, didn't think to clean them, so cleaned & the new clutch plate fits n moves/slides perfectly, so the box when back on with no issues, almost fell into place straight up to the block with no resistance, so leaving the centre exhaust section & prop shaft off I quickly started it up & engaged all gears with no issues, used a one way pipe bleeder but will get someone to operate the pedal & do it old school to make sure all the air is out, reverse did crunch a little but maybe once bled again it may be ok as was originally.
So hopefully all will be ok, I'll put it all back together & see how it drives. Thanks again all, Oh my ears are still ringing but not from running the car with no exhaust but from my wife ringing me in the garage after I switched it off & bollocking me for trying to pi55 off our neighbours! ;-) , it was 8:45pm !
 
Glad to hear you found the issue. Hope your test drive goes smoothly. Won't be too long now before you'll be posting pics of your completed restoration. I for one am full of anticipation!
 
Hi All, many thanks for all the input, much appreciated :), So new SD1 clutch plate ordered from MBGD parts, much better quality then the one I fitted in 2019 when I did the conversion, anyway I thought I had checked the movement of the old plate on the input shaft splines but I had used my spare shaft , so naively thinking all was good, then Stu said "Have you tried it on the actual box splines or just your old input shaft, wasn't sure by what you said. " Ahh so checked the old plate on the g/box splines & could only just get it on, no back & forth movement....so that'll be it then & explains why it was so hard to get the engine to fit flush against the bellhousing last month. Also the g/box input shaft splines had got dusty/dirty from my engine bay clean up, didn't think to clean them, so cleaned & the new clutch plate fits n moves/slides perfectly, so the box when back on with no issues, almost fell into place straight up to the block with no resistance, so leaving the centre exhaust section & prop shaft off I quickly started it up & engaged all gears with no issues, used a one way pipe bleeder but will get someone to operate the pedal & do it old school to make sure all the air is out, reverse did crunch a little but maybe once bled again it may be ok as was originally.
So hopefully all will be ok, I'll put it all back together & see how it drives. Thanks again all, Oh my ears are still ringing but not from running the car with no exhaust but from my wife ringing me in the garage after I switched it off & bollocking me for trying to pi55 off our neighbours! ;-) , it was 8:45pm !
Glad you've got it all sorted, I bet that's a relief.
Made me more paranoid when i fitted my box yesterday then discovered today I've fitted the wrong clutch release bearing carrier so it's got to come apart again.
 
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So all back together have covered about 13 miles, gear change is nice but just cant it to run nice without the choke out slightly, tick over doesn't sound great almost hunting slightly , timing is set to factory 6°BTDC, tuned the carbs as good as l can get them, they've had all new rubber seals, o rings gaskets, didn't do floats or needles.
Without nailing it too much as running in but certainly does fly , instant pickup but with choke out!.
I took the dashpots off tonight and noticed the n/s carb needle holder is missing, it keeps the needle central when fitted to the dashpot ? and his held in by a small screw fitted on the side of the dashpot, would this effect slow running? it ran rough when I first bought the car, when I removed the heads in 2021 I saw witness marks on top of one the old pistons and corresponding head chamber where a foreign object had clearly gotten in there, possibly the missing needle holder.
Went for a short drive on Monday eve, timing was out slightly and the oil pressure didn't seem great when l took it for a 3 mile drive tonight, am l being over cautious perhaps? but l'm more concerned about the 'squeaking noise' . Oh the bloody bonnet is stuck now so more adjustment
 
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So all back together have covered about 13 miles, gear change is nice but just cant it to run nice without the choke out slightly, tick over doesn't sound great almost hunting slightly , timing is set to factory 6°BTDC, tuned the carbs as good as l can get them, they've had all new rubber seals, o rings gaskets, didn't do floats or needles.
Without nailing it too much as running in but certainly does fly , instant pickup but with choke out!.
I took the dashpots off tonight and noticed the n/s carb needle holder is missing, it keeps the needle central when fitted to the dashpot ? and his held in by a small screw fitted on the side of the dashpot, would this effect slow running? it ran rough when I first bought the car, when I removed the heads in 2021 I saw witness marks on top of one the old pistons and corresponding head chamber where a foreign object had clearly gotten in there, possibly the missing needle holder.
Went for a short drive on Monday eve, timing was out slightly and the oil pressure didn't seem great when l took it for a 3 mile drive tonight, am l being over cautious perhaps? but l'm more concerned about the 'squeaking noise' . Oh the bloody bonnet is stuck now so more adjustment
Glad you got your clutch issue sorted, and like Harvey said that probably is causing it to run lean so the chokes richening it up a bit.
 
Fitted and vastly improved, just need to tune it again. One thing that niggles me is when the engine is running and l undo the oil filler cap l can see no oil being pumped throughout the rocker shafts, oil pump is the uprated version which l had on my red P6 and from memory l could see vasts amount of oil flowing and l guess running down to the camshaft, not happening on this newly rebuilt engine, rocker shaft assemblys are original but throughly cleaned, lot of black old gungy oil came out. Possibly they are blocked and not allowing the oil to flow correctly,
? am l correct in saying it should also run down into the valley and lube the camshaft and lifters ? l did prime the engine using a proper tool fiited to an electric drill and l even removed one shaft assembly at a time and oil spouted out the oil feeds on both sides of the engine. Maybe im being paranoid but after spending £3k on a full rebuild l dont want to kill it after 16 miles, oil pressure is spot on though
 
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A bit of paranoia is surely better than a prematurely knackered engine! Maybe whip off the rocker assemblies and blow the oil ways in the pedestals through with compressed air? Or poke wires through to dislodge any debris? You should be seeing a fair amount of oil making its way up to the rockers, and yes, I think it is supposed to drain back down the valley to the cam and lifters. I dimly recall reading in the Des Hamill 'Tuning RV8 engines' book that some folk polish the valley area of the block to speed oil return. I expect more knowledgeable members will be along shortly to disdain my conjecture and tell what to do! Hope it turns out to be a small blockage that is easily removed, and that you get to enjoy worry-free revving soon!
 
Ive never seen oil being chucked around the rocker shaft when removing the oil filler cap.
Sleep well DamianZ28.
Oh ,did I mention Im no expert on oil and rocker gear lubrication.
 
When I rebuilt my engine, I primed the oil pump with a battery drill. Oil came out of the rockers within a couple of seconds, so I would certainly look into this. Try removing the rockers covers and run it up to see if oil is getting through.
 
Thanks for you input guys, probably getting a bit fuzzy in trying to remember stuff from my old P6 which I sold 8 yrs ago lol.
So ongoing engine stuff, removed the rocker shafts & plenty of oil in the shafts & definitely loads oil spurting out of the feed ways when using the oil priming tool.
Have done about 27 miles running it in, took it out last Friday for a quick run but upon start up it just didn't want to run on all 8, once driving it was fine. Oil pressure through the roof but once warm it was shite, l wonder if the spring in the pressure relief valve is weak due to being old and is letting the valve open to early which makes it worse when hot? Valve isn't stuck as checked it. .also my coil is a cheap version so wonder if that's why it ticks over really rough. Plenty of fuel getting in, new needle valve holders fitted etc. Will get a new coil and have ordered tadpole style relief valve and spring from JE Developments. Also will replace the oil gauge sender as probably nearly 50yrs old.
It'll get there once all the 'teething' issue are sorted. by that time fuel will be £3 a litre but hey its temporary rise, considering all that is happening in the Ukraine then its a very small price to pay indeed compared to the unbelievable situation they are facing on a daily basis.
 
If you replace the pressure sender, don't throw the old one away. New ones are not very good, and you may find the old one is actually better.
 
Fitted new tadpole uprated oil pressure relief valve plunger and new spring which is slightly stronger but not over the top. So went for a 8 mile ish drive, once hot again shit pressure like 15psi at about 45mph, almost 0 when on tick over with oil pressure light on, blip the throttle and goes straight out. No horrible knocks or rattles or smoke, no lifter tapping either, engine not even getting too hot, still pulls like a steam train in a cautious manner as still running in. Baffled though, either dodgy oil pressure gauge or faulty oil pressure sender
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One person has mentioned the oil pump itself could be playing up, I have fitted the uprated kit with the taller gears, when l checked the flow the other day it was spurting out of the top of both heads (rocker shafts removed). Saying that though when l fitted the uprated kit whilst the engine was in bits l did the dry run to check tolerance but it was way to tight as in the actual gear on the disty drive shaft wouldn't rotate at all, so l had a mere smidgen taken off the bottom of the same gear so it would rotate but l may have taken too much off as l then created slight up and down movement on the gear shaft when assembled
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, not even a millimetre but would this effect the pressure once hot? Do the tolerances need to be incredibly tight when the bottom pump cover is fitted? I was worried that the shaft drive was too tight and be damaged in operation or the disty shaft get damaged too. Possibly l now need to replace it..?
Can of petrol n match will fix it...
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..swap it out for a 5ltr small block yank motor will defo sort it
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pressure like 15psi at about 45mph, almost 0 when on tick over with oil pressure light on, blip the throttle and goes straight out.

That's two different senders, one for the gauge, and one for the light, so low pressure on both is less likely to be faulty senders, although that's not impossible. As suggested previously, get a known accurate master gauge on it before going any further.
 
The oil pump gears need to be VERY close to the end cover even small discrepancies will cost you a lot of oil pressure. Anything near a mm is way to much. For your extra length gears do you have a spacer fitted or are you using a later cover? Spacers also need to be very closely aligned
 
IIRC without the cover on the pump the gears are PROUD of the casting by @ 0.005" or so, the gasket then provides the running clearance. So a gasket of @ 0.010" will give a running clearance of @ 0.005".
If you can feel end float on an assembled pump then I am thinking you have too much clearance.
Of course this matter is complicated by the use of a spacer plate and multiple gaskets when fitting an uprated kit.
 
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