proporsche Posted June 29, 2015 Posted June 29, 2015 Hi Rock: sorry to hear your trouble.I have a Q.In what rpm did you feel the vibration?Was it at 3000? How many miles you put on before 100 mile service? After rebuilding the first drive was how many miles? Ivan
Dr Rock Posted June 29, 2015 Author Posted June 29, 2015 Hi Rock: sorry to hear your trouble.I have a Q.In what rpm did you feel the vibration?Was it at 3000? How many miles you put on before 100 mile service? After rebuilding the first drive was how many miles? Ivan Before the rebuild, the engine would be a touch rough at 3-4k rpm - after the rebuild it was silky smooth at all rpm. When I picked up the car 2 weeks ago the vibration was all the time. The garage later said it was maybe more pronounced at 3000 rpm... The garage put 10 miles on it before I picked it up, I drove it 13 miles home to change the wheels from winter to summer ones, put the arch liners on, the skid plate, change the rear bumper etc. Then I did 100 miles one day, 150 miles the next day, 286 the next day, keeping the revs moving up and down, lots of engine braking and not going over 3.5k rpm, changed the oil and filter at 559 miles and did 444 miles the next day, taking the revs up to 4.5k rpm. Then I took it back to the garage (13 miles), giving a total of 1016 miles done before its final checks and oil change.
MaxDiesel Posted June 29, 2015 Posted June 29, 2015 I showed the picture of you main bearing shells to someone who knows a bit about engine bearings for a second opinion, his thoughts were: He's seen these washboard wear lines before, more commonly on larger engines, and usually on engines that haven't failed In his experience the root cause of these wear marks has been with the machining of the bearing shell shape... possibly caused by wear in the bearing race of the fine turning head that completes the bearing machining op, leading to a very shallow (microns in depth) waviness around the bearing. In his opinion the level of marking on your shells wouldn't be a durability/failure risk but may increase sensitivity low oil pressure, dirt, etc.. Overall he thought that even though the bearings look rough in the pics, in reality they are not that bad and he wouldn’t expect the driver to notice anything resulting from this... He didn't think it looked like a 'tight' build either - I would have thought if it had been tight it would have been more noticeable in the first few minutes/hours of running, not after a 1000 miles. Have they found anything else that could have been the cause of the vibration ?
Dr Rock Posted June 29, 2015 Author Posted June 29, 2015 Don't know any more: I'll pay 'em a visit tomorrow afternoon and find out the make of bearing and where they came from, ie OPC or aftermarket. I'll also ask about the conrods and their bearings. Agree with all you have said and many thanks for your interest! Anything to get to the bottom of this mystery is appreciated.
GaryH Posted June 29, 2015 Posted June 29, 2015 Isn't vibration going to be caused by imbalance/something loose so unbalanced pistons/crank, loose rod bolts?
daveuxb Posted June 30, 2015 Posted June 30, 2015 Hi Dr Rock Been following your build. Really sorry to hear about your run in period. My 1st question would be was you crank polished or machined and are those standard or oversized bearings? They look beefy to me and could be the o.25 oversized ones.
daveuxb Posted June 30, 2015 Posted June 30, 2015 (edited) p.s. I'm no expert, but id be interested to know how much was machined off your crank and what size those bearings are. To me there looks to be clear contact there and that there is insufficient clearance for the oil to do its job, i.e. provide a decent hydrostatic pressure btwn the bearings and the hard bits. Edited June 30, 2015 by Von Twinzig
Dr Rock Posted June 30, 2015 Author Posted June 30, 2015 Crank was just polished AFAIK. Been to see the engine bits today- the good news is the crank and rods are all OK, just not arrived back at GCR yet. So that means all the big expensive bits are all good to go again. Bearings were genuine Glyco ones from Nottingham OPC, so not aftermarket not-so-good quality ones. Big end bearings were worse than the main bearings. Some more pics for you: Pistons and rings are all OK:
Dr Rock Posted June 30, 2015 Author Posted June 30, 2015 (edited) So sh*t bearings or oil starvation? The latter, but quite how? Stumped. Edited June 30, 2015 by Dr Rock
Nige Posted June 30, 2015 Posted June 30, 2015 The latter, but quite how? Stumped. Down to the build then, hope GCR stand by their reputation on this.
Dr Rock Posted June 30, 2015 Author Posted June 30, 2015 Down to the build then, So how come everything was fine for 1000 miles?
Nige Posted June 30, 2015 Posted June 30, 2015 Cos it took 1k for the bearings to get like that with not enough oil. I don't know? Just spouting random sh*t.
Dr Rock Posted June 30, 2015 Author Posted June 30, 2015 Cos it took 1k for the bearings to get like that with not enough oil. I don't know? It took < 4 miles at low speed and rpm's to do that. Just spouting random sh*t.
David Gander Posted June 30, 2015 Posted June 30, 2015 Maybe sprouting nonsence but was the oil pump primed, possible air lock? The old fashioned way was to pack the oil pump gears with Vasalene to ensure no air. If that practice is no longer done these days, was the engine turned over sufficiently before firing in order to have clearly high oil pressure? When I fitted a new turbo unit to mine, the oil supply line to the turbo bearings had to be disconnected first to ensure that there was sufficient flow with no air-lock into a receptical before refitting the oil line, this is of course turning the engine over without firing. Could the damage be done in the initial stages of firing up? Maybe talking out of turn but just thinking.... Regards, David.
Dr Rock Posted June 30, 2015 Author Posted June 30, 2015 The engine had just done 1000 miles in 4 days with no problems, so even with an oil change I can't see how the pump could suddenly fail to work?
carbon749 Posted July 1, 2015 Posted July 1, 2015 Based on everything you've said, and you have dismissed the majority of suggested reasons, due to the 1,000 mile before the oil change being ok .... With problems only occurring after the oil change ..... Maybe the oil change is too blame ??? Was the right oil used? Was the oil used, correct for a newly built engine ? Was enough oil put in? The fact that you only had issues after the oil change, does make you wonder if this had an effect on the engine? Was the engine tight before the change, but, ok on 10W-40, but, a tight engine with 10W-60 may not be ok due to the increase in viscosity.
ab54666 Posted July 1, 2015 Posted July 1, 2015 ..........checked the head stud torques and replaced the oil lines and thermostat. Sorry to hear all this Fraser, outside of oil change you mentioned they replaced oil lines/thermostat as being the only other oil related work, any chance this has had an effect, I assume the oil could have been drained out, therefore when they refilled the thermostat would be closed with potentially no oil after, not sure how much runs in the lines and down to the cooler but could that be a reason for starvation...??
Leicestershire Posted July 1, 2015 Posted July 1, 2015 Very sorry to read this. Hope you find the problem and get engine that all the hard work deserves. Just thinking outside of the box a little. Did you change the pressure relief valve? A dodgy one may be OK on thinner grades of oil but increasing the viscosity could cause the sump to flood and the pump to cavitate. This would result in oil starvation.
Dr Rock Posted July 1, 2015 Author Posted July 1, 2015 Sorry to hear all this Fraser, outside of oil change you mentioned they replaced oil lines/thermostat as being the only other oil related work, any chance this has had an effect, I assume the oil could have been drained out, therefore when they refilled the thermostat would be closed with potentially no oil after, not sure how much runs in the lines and down to the cooler but could that be a reason for starvation...?? Interesting, but the problem was immediate on start up, ie cold, so *way* before the thermostat opened. Very sorry to read this. Hope you find the problem and get engine that all the hard work deserves. Just thinking outside of the box a little. Did you change the pressure relief valve? A dodgy one may be OK on thinner grades of oil but increasing the viscosity could cause the sump to flood and the pump to cavitate. This would result in oil starvation. 2 relief valve springs are on the invoice...I'll ask and see what Chris says.
Richard Bernau Posted July 1, 2015 Posted July 1, 2015 Exactly. GCR have built enough of these engines. You just have to trust your engine builder to fix it and give you a good engine. Maybe they did something different from their usual and just won't say, who knows. As soon as you start second guessing them, they will be more likely to wash their hands of it. Right now you are in a position of reliance and trust and you should keep that dynamic so they feel they have to fix it no matter what. You have already been massively inconvenienced by their screw up, so they should be bending over backwards now to make you happy. When you get it back you just have to drive it like you stole it and enjoy. I know we all like to analyse and speculate what might be wrong, but once you get it back in rude health, it kind of doesn't matter.
Dr Rock Posted July 2, 2015 Author Posted July 2, 2015 ^^^ Exactly Photo update - crank and rods are back, bearings and crank are standard, not over/undersize. Crank all polished and yummy: Rods are fine, just need bearings: No.6 was deemed the worst: But I reckon No.3 is worse: Barrels are lovely:
strosek34 Posted July 2, 2015 Posted July 2, 2015 Do they have any clues to what caused the problem Fraser.
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