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Lotusfab

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Everything posted by Lotusfab

  1. I visually inspected the followers. I know of several builders, now I have started to investigate, who Ping them. If the sound is dull they are replaced. In my case the engine had a catestrophic faillure and was rebuilt in 1987, the entired bottom end was replaced. Maybe they reused the top end parts and this follower had been weakened by the previous Failure? The car did hardly any miles after the rebuild and was put of road. I have the reciepts for the work. I will check the sludge as I still have paper towels with it on.
  2. The damage on my bearings and surfaces is consitent with that caused by cast iron particles. The are no signs of glass bead damage on the parts. I have the oil startvation damage on the main bearings. I believe the oil pump is a red herring. The initial starting didnt effect the engine probably because of the graphogen. It run well for two months. Then the cam follower started to break apart. The bits circulated in the oil and caused bearing damage. This caused the oil pressure to drop when hot. On my return from Brooklands I noticed the pressure had fallen below what it usually is - I putbthis down to the engine being hot. Finally the camfollower broke apart. The oil pump damage was caused by the cam follower. I would have noticed it and I had all the parts inspected by someone else who also would have spotted it. So this was caused by using old cast iron cam followers! I'm definately getting it rebuilt. The only question is whether me or someone else is going to do it! Im pretty certain now this was caused just by a cam follower breakup. I wont make the mistake of using cast iron followers if I do this again!
  3. I have found a website that has pictures of bearing shell damage. Using this info I think I finally understand what happened. The marks on the shells indicate two types of wear.
  4. I examined it quite closely. It had tiny granular fragments of iron. It may have bead I need a microscope! I guessing ground up cam follower! The piston, rings and liners seem unaffected. The big end journals have very slight damage which will polish out. The front main bearing journal has deeper scoring. It will need a regrind. All the bearings must be replaced. The camshafts must be replaced. One of the cam towers needs replacing the other might be ok. The Auxillery housing must be replaced. Almost a new engine!
  5. You make some good points. The engine ran quite well for two months. Not sure how many miles I covered
  6. Im not 100 percent on what caused this. The only hard evidence is the cam follower breaking up. The pump wear and the rest may have all been caused by this one thing. Well the bottom end is off. Pistons and bores appear ok, but need measuring. All bearings have scoring and must ve replaced. Big end journals need a regrind. A lot of cash! Im not sure whether I want to rebuild thie again. The amount if effortand time I spent this should not have ocurred. Im asking myself if I should just go on holiday, get an expert to do it and come back to a new engine! That way if it goes the same way its their fault! Oh well Imhave a think about it!
  7. To be clear though I was getting 75 PSI from the pump at start, when I sorted the PRV. There must have been a lot of damage in a very short time span.
  8. I would have done but Ive already cleaned it! It just looked like a darl grey sludge. Maybe graphongen mixed in from the rebuild. And this was after the rebuild. My gut tell me blasting media and metal in there. Heres the Oil analysis as promised.They told me the Boron is probably due to oil additives. So no concerns from this report. Have to remember though where the sample came from and it only detects small particles.
  9. Just got the sump off. Shocking! Theres pariticles in there that must have cause the scoring. Whether they are blast bead, cam follower bits or a combination I dont know. I have never seen that in an engine especially a rebuilt one! I will have to think carefully how to proceed. I cant have this happen again. Now I have seen a good oil pump its obvious the one one there was worn. I cocked this up. I should have examined the oil pump more carefully and not started this engine without oil pressure hoping it would come up! If your reading this dont make my mistakes! I will have the crankshaft out by end of today. The oil report came back with nothing unusual, but dont forget it cant detect large particles, there were a lot of the in the sump. It was like a grinding paste!
  10. Yep, I'm replacing the rotor and annulus with new. I also have a replacement auxillery housing and oil pump housing thanks to Andy on here and its in very good condition compqred with the existing one. Im lucky and have four micrometers and all the other kit needed to measure all of the components on the engine. As far as the cam housings I really need new camshafts so I can measure the housing to cam clearance and determine whether honing is practicle. Ill take the bottom apart tomorrow. Im really not looking forward to that!
  11. I am busy prepairing Andys auxillery housing and pump which will be used. Im thinking ifbreplaceingbthe rotor and annulus with new. Has anyone used the new ones, there are a few adverse stories? No sure how much will need replacing yet, early days. I have to measure everything again.
  12. Thanks Dave(Lotusman) Awesome test rig. Wouldnt fit on my turbo inlet manifold, but I just happend to have a spare S1 manifold. After testing the pump jet operation I would never bolt any rebuilt carbs in a car without calibration. One carb had no output! After adjusting I found myself screwing the adjusting screw way up the thread. The pump jet spring has gone weak and needs replacing. The other side the spring is passing through the pump jet arm! New springs and it will be really easy to calibrate exactly. Thanks Dave!
  13. Yep, unfortunately is going to mean a very big bill! Replacement camshafts and maybe both towers( exhaust tower might be ok) cylinder head new valves, guides, seats Maybe new pistons and liners, conrods. Crankshaft, might need regirding, balancng and new bearings. all new seals ouch! Have already sourced all of the parts needed to rebuild. But even after that all Im still cost even over paying for a proffesional rebuild! Plus I will have effectively a new engine! Has anyone used new 107 QED camshafts? Just wondering how they comoqrevto the originals.
  14. Should be all apart by the end of tomorrow. Then, cleaning, mesuring and rebuilding.
  15. Thanks chaps, Barrys picture link is quite convincing. Theory One The intial start , with the PRV stuck open and no oil pressure, must have caused excessive wear. This resulted in wear particles in the oil system. These then caused the deep scoring. Theory Two The iron cam follower started to break up releasing partcles into the system. The engine ran like this for sone time. These paticles started to score and cause damage. The engine stoped when the cam follower completly failed. Im almost ready to test the old pump ouput against a new one. I have removed the sandwich plate and bolted the filter directly on. Its refilled with new oil. I have a drill to power the pump. Once this is complete I will take the sump off and insect the bottom end. I expect to find the same scoring. If there isnt any I'll have to rethink. If this was all caused by the PRV and oil pump Ill be very pleased. A simple omission on my part (oil pump PRV) check,which isnt in the Turbo version of the manual, will have caused this with the rest of the rebuild all good! Anyhow this time I am going to build a much better engine. I plan on balancing the crank with the flywheel and clutch. Should help out with the high rpm dyno testing! Any other theories out there?
  16. My question now is could this scoring be cause be caused just by lack of oil? Im not sure but it seems like contamination. The oil test is not conclusive as it only detects very small particles, much smaller thatn the glass bead. The sample came from the sump which was checked with the microscope. I should have saved some of the cam oil and tested that as well or got a microscope! The good news is with no sump contamination Imdontbhave to throw away the new oil cooler pipes and the rebuild will be easier.
  17. Possible. Was just told by the lab the dilution was only 0.3 per cent. So the drop in oil viscocity was not due to fuel. They said the drop in viscocity might be due to overheating.. This is difficult now as I measured the water temp as 90 degrees max at the sensor. The report comes out tomorrow the microscope showd only a tiny piece of bearing ( not good news) no glass bead. He suggested oil starvation which brings us back to the PrV not wotking correctly. I need to test the pump.
  18. All of the valves clearances were measured and checked. They were in spec. Maybe the range means you can have some oily deposits and its acceptable? Anyway Its not upmto my standards so im replacing everything. I will look into the Gary Kemp valves with sealing washers. Not sure if they are suitable, will have to research it.
  19. Prv was stuck open when I first tried to start after the rebuild. I realised this was why there was no oil pressure. I took it off cleaned it and put it back then gotboil presure. When I first took the engine apart I found the pick up strainer araldite had broke up. The new thing here is fuel in the oil, how did it get there? Was this responsible for the failure? Its certainly not normal. Hopefully the report will enlighten me.
  20. Also Im not happy with the combustion. Its not clean enough. I suspect oil getting in on valve guides. Time to get the head completely redone. New valves and guides. Thre doesnt appear to be any valve guide oil sealing on this head?
  21. I have started to do a 180 in thinking. I have just found petrol traces around the no2 piston area. Could this have been as simple as the cam follower breaking up? The change in inlet clearance allowing unburnt fuel to leak into the oil. Oil thins, lots of wear on rest of the engine. Residue from cam follwer causes scoring?
  22. Oil analysis Reports not out yet maybe later today. I spoke to the lab techniician. Surprising reults. He said the silicon content was within normal parameters but the test only identifies small particles. He is going to check for glass bead in the oil with a microscope! Really interestingly he said there may be an issue with fuel in the oil that has thinned the viscocity!! . I noted a misfire on number two when hot, that wasn't there before when at idle. This only happened recently. This is the cylinder that had the cam follower failure on the inlet valve. He also said the oil smelt of fuel! Could it be somehow fuel has diluted the oil to such an extent to cause wear? If so how did this happen? Was it a symptom ofbthe inlet cam follower breaking up? Maybe as it started to go it affected the inlet valve clearance. There was a strong smell of fuel which wasnt there when the car was first run. I thought it was loose filler caps, which I fixed. Pleased I seem to be getting somewhere now. Thanks to Dave his carb set up kit has arrived, thanks mate! So I should be able to calibrate the pump jets correctly. Will post the report when it comes out.
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