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OzCoupe72

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Posts posted by OzCoupe72

  1. Thanks guys, great to have your input and will take it on board once I get my engine back

    I have raised it with the machinist several times to go to the larger end of the clearances and he seems to think .0020 - .0025 is fine

    I will double check it with plasti-gauge though

    He reckons the thrust(end play) will be about .007 - .009 which I'm okay with

    Unfortunately I don't have expensive micrometers or bore gauges so just had to go with plasti-gauge, dial gauge and feeler gauges

    Was pretty anal with being clean and everything turned over smoothly

    The only thing we can point to is the clearances and unfortunately my memory doesn't serve me well as to how I determined what the clearance was

    I don't doubt that I blew it in this regard but I do doubt that a tight bearing clearance would result in a sudden loss of oil pressure

    It's been a long anxious wait and I just want to get my vehicle back on the road again

  2. I know that this is splitting hairs but how all the gear heads around here do it.

    We put the bearings in the rods and block and torque them to spec. The we measure the actual bearing with an inside micrometer and grind the crank to fit the bearing. We never just grind it .010" or .020" under standard dia. Yes it is usually only a few tenths of a thousandth but it is right. 

    When we raced small engines in carts we set the clearance by using a roller burnisher and you could size the rods, wrist pin holes right to a .0001" easily. Roller burnisher for diameter of rods and crank mains would be expensive. 

    Like you my short term memory is gone, lol. Didn't go back and read it all. Are you sure that you got all the oil passages spotless clean? A little bit of grit in there is a bad thing.

    When they did the cash for clunkers deal they poured the crushed glass in the oil. Was talking with guy at local dealer he said most Japanese cars would seize in less than a minute. He had a Ford 300 6 cylinder run for 30 min. before it seized.

    As the crank was brand new there was no need to grind it

    The mains tunnels were align honed, block zero decked, fully balanced, new rods etc. Machinist supplied pistons, rings, bearings etc

    Not sure exactly what the machinist measured but as I wanted to assemble the block myself I just used plasti-gauge to check it and unfortunately I must have used the OEM clearances.

    If I had of gone with "performance" clearances then it would have been just a matter of purchasing ACL H series bearings which I think are .001 oversized then mix and match until acceptable clearances achieved

     

    All good in hindsight to speculate, and boy oh boy have I done that, but the fact remains is I failed to get the right clearances from the start

    The blocked was thoroughly cleaned including using rifle brushes to clean the oil galleries, flushed several times and blown out with compressed air

    I can only hope it was just tight clearances that caused this but having no proof leaves me wondering, fingers will be crossed!

  3. I wish I had all the answers, believe me I do!

     

    Spike - the machinist probably removed the centre main cap first and assumed the worn thrust was the main issue however after further investigation both mains and rod bearings were prematurely worn so his diagnosis moved from a thrust failure to bearing failure due to tight tolerances which lead to a cylinder(no 4) failure with minor scuffing on the other cylinders, obviously due to lack of oil pressure

     

    When I assembled the engine the thrust clearance was the first thing I checked and it was certainly within specifications as were the bearings

    The question is what specifications did I use?

     

    After many nights with little sleep trying to get my failing memory to work I realised I may have got my clearances from a book by George Reid called - 351 Clevelands How To Build For Max Performance so I had a look and there is a whole page with most clearances/torque specs

     

    Upon looking at the recommended bearing clearances it had approx .0009 - .0015 which I now know is not for performance builds but OEM stock specs

    I had a vague memory of how wide the plasti-gauge was and sure enough it was about .0015 or possibly less

    The thrust clearance would have been within OEM specs but shouldn't be an issue however if I did have my rod/main bearing clearances at OEM specs then this could cause a problem with a performance build

     

    IA Rider - it was a brand new Scat crank and was checked by the machinist, journals looked perfect to my untrained eye

     

    Anyway I've gone with boring it to .030 over, new set of SRP pistons (ouch!!) and the crank is being ground to suit new bearings with clearances at .002 rods .0025 mains

     

    Hopefully have the block back by the end of the week and on the road following week but it will be a nervous first few hundred miles

     

    Oh and lucky I got my C4 trans checked out, nothing wrong with how I put it together but the front band and a few clutch plates show some feathering which is probably due to old(new) parts getting moisture in them. This could have caused some issues so getting them replaced

  4. Sounds like flooding and due to the fact it has been sitting around for a while the needle & seats are probably sticky

    Perhaps just replace them and readjust your float levels

    What carby is on it? Maybe others can give some tuning tips?

  5. Usually only have to use a spacer shim for manual cars

    I would be checking what flex plate you have first

    From memory if you fitted a 157T to a larger(164T) bell housing your starter probably shouldn't engage at all so maybe not that

    Make sure it is a C6 flex plate as they have a different offset to C4

    C4/FMX flex plate the convertor mount point is flush with the engine side of the ring gear and C6 is flush with the trans side

    Whether any of this affects your starter not sure, good luck

  6. You're turning out some great work and becoming quite a good panel beater

    Sometimes will need to apply heat and cold to shrink some high spots especially when you get that annoying "tin can" effect

    I have a shrinking disc I put on the sander, it is more subtle than using flame, takes a little getting used to but certainly worth it

    Like me you will do everything to avoid buying a new fender and paying huge shipping costs, not to mention having to rework the repop panel

  7. Congratulations on reaching this milestone, something I wish for

    It's usually a process of sorting out the bugs and other issues after a rebuild or restoration

     

    I managed about 10 miles and the power steering hose blew, destroying the pump

    Next time got to 70 miles and the engine failed

     

    Good luck with your Mustang and hopefully you reach many more milestones

  8. Bloody hilarious Midlife, at least she had the steering wheel on the "right" side!

    Maybe she needs to watch this video -

     

    1sosatic - I have had a similar experience

    A young a-hole in his shitbox Toyota Hi-Lux that wouldn't pull the skin off a rice pudding decided he would show me why his wedding tackle is inadequate by passing a Mustang into oncoming traffic at over 60mph.

    Luckily I was watching this "Darwin Award" candidate tailgating me, once I saw him move I immediately slowed down and moved across to the left, the oncoming traffic also did the same and the oxygen thief survived another day.

     

    In the short time I've had the pleasure of driving my Mustang it certainly gets plenty of attention, unfortunately not always good as above

    But it is all worthwhile when you get positive comments such as the kids down the road and their mum waving me to come over and ask what is that "gangster" car

  9. I'm hoping the machinist has already checked this

    I could not see any cracks and pick up was tight with correct alignment/clearance

    I'm certainly no expert but would expect if clearances were the sole cause it would have been a more gradual progression with some contamination in the oil especially after the dyno session but this was a sudden drop in oil pressure

  10. I also agree it may not be the bearing clearances that caused this but this is all the machinist can come up with so far

    He reckons number 4 cylinder/piston (wasn't seized just badly scuffed all the way around) was due to the lack of oil pressure

    Cam bearings not bad but will be replaced

    I will get all the old parts back and post some pics in a few weeks

    We've pretty much eliminated 95% of all possible causes so far but will be persistent in getting an answer

    I can only hope he finds something conclusive and I don't have to pre-book the tow truck next time!

  11. The "window" is probably spring loaded but never having taken one apart could not advise on this

    If it was me and it didn't free up with some lubrication I would probably replace it

    To lube the cylinder best to use powdered graphite, just put the nozzle in and squeeze a puff of it in, some on the key can help, push it in a few times

    Yes there is a gasket between the door and cylinder and would use this, if no gasket water will get in

    I bought a complete matching lock set but you could also get a locksmith to re-key it for you and they may even be able to fix the cylinder but I suspect they could charge more than it is worth

  12. Did you or the machinist measure the volume of oil that remained in the oil pan?

     

    Don - I drained the oil before removing the engine, dipstick was on the full mark and about 6 litres came out with a little remaining in the pan and filter

    Oil was contaminated no doubt mostly due to number 4 cylinder and there was a small amount of oil in this cylinder

     

    I suppose if the clearances were too tight it would cause the bearings to overheat and since this was the first drive over 10 miles distance they finally gave up with the loss in oil pressure scouring the cylinders

     

    Unfortunately there is no way to confirm what exact clearances were on the bearings as they are all shot

    This is a mistake on my behalf and although I've had success in the past with plasti-gauge I won't be using it again except perhaps to check how accurate it is once I get my short block back

     

    Hopefully will have it back on the road in a month or so and it will be a nerve wracking experience driving it for a while without a 100% conclusive diagnosis

  13. Still nothing conclusive and machinist still holding to the clearances theory and maybe he's right?

    Chuck - you're right it is a difficult one and even the machinist is not overly confident but will be checking everything

     

    Both mains including thrusts and the rod bearings failed which to me is oil starvation and perhaps if the clearances were a little tight that would certainly have contributed to the bearings early demise

     

    One thing that gives a hint of oil starvation is the oil filter when removed had very little oil in it

     

    TommyK - No oil mods, not necessary for a mild build and standard volume Mellings pump 85 psi cold, 75 psi at revs and 45 psi hot idle

     

    Jay - Oil pickup to pan clearance was spot on - can't remember but maybe 3/8 inch and machinist did also check this

     

    Anyway I have 2 choices to fix this

    One was to sleeve no 4 cylinder, new piston, grind crank, new bearings, rings etc

    Second option was to put all new pistons boring it to .030 which would not need a sleeve but this option would cost about $500 more and I would rather keep my block at .020 o/s to leave room for future rebuilds so will go with the first option

    Only issue is will have to wait a couple of weeks for a piston from the USA

    I only wish my memory was good enough to remember the exact clearances I came up with, next time I will record everything!

  14. Hi David

     

    Cam/lifters looked fine but yet to remove cam, machinist will do this

    Pistons were clearanced by the machine shop and he is certainly aware of the need for extra clearance for forged pistons

    Ring gaps were filed to spec although I did file a little too much off a couple of compression rings but this wouldn't cause any issue

    Machinist reckons piston/cylinder wear due to oil starvation

    Pistons perfectly centred, crank end float spot on and rod side clearances spot on

    Not sure on mains, ACL Race series I think 1/2 grooved?

    Machinist reckons cam all good but hasn't reported on cam bearings yet, lifter bores look good but will double check this and front cam bearing

     

    I have assembled half a dozen Ford V8s always checking bearing clearances with plasti-gauge and never had an issue

    Plasti-gauge while not very accurate will still show a pattern and from memory there was nothing out of the ordinary

    Unfortunately with age my memory not so good and don't remember exact clearances but would expect with all new components they would have been slightly on the tight side. Everything rotated freely 

    I have my doubts that a slightly tighter clearance would have caused a sudden failure but I could be wrong

    Perhaps it's the chicken or the egg question - did the oil pressure drop first causing the damage or the other way around?

    Thanks for your input, will post more info if/when it comes to light and hopefully get a better night's sleep!

     

     

     

     

    Carolina_Mountain_MustangsWhat does the cam and lifters look like? Did you use zinc additive in your oil?

    When I worked in race shop you opened up the clearances for couple reasons. The flow of oil cooled the bearings for car that run on track for 500 mile races. The other was pure friction reduction. What we saw with too much oil pressure was that the bearings eroded looked just like when water washes out a section of soil. Most people are not looking at engines that are ran at max for 500 miles and do not see this. A 1/4 mile engine will probably never make it 500 miles. We ran pumps with higher volume not necessarily high pressure. 

    We never ground the cranks to the factory numbers. We would get the new bearings and install them and mike the inside diameter of the bearing. The boss would then tell the crank grinder what diameter to grind each journal. They would vary sometime .001" from the spec. number but usually a few tenths of a thousand of an inch. 

    I would double check the clearance given for the pistons and check with the mfg. for the proper clearance. Some forged pistons need extra clearance due to expansion being more than a cast piston. 

    Did you grind your ring end gaps or just put the rings on and slap the pistons in? Rings might have been butting ends and caused scuffing of the walls.

    I think one of the members had an issue with the journals on his new crankshaft not being aligned with the bores of the cylinders. Do you have pics of the bottom of the engine when you assembled the first time? When he bolted the rods to the crank the small end of the rod was not centered with piston. 

    Also check the clearance on the lifters. Being a wet lifter galley if there is excess clearance there all the oil leaks out around the lifters starving the bearings. 

    The position of the front cam bearing is also important. 

    Did your main bearings have oil grove all the way around or 1/2 way. My old boss preferred the 1/2 way around. 

    For sure you do not want to go back together with the engine and do the same way as last time. Will probably get the same results. 

    I am suspect of end gap on rings being cylinder issue then the resulting crap gets into the oil and causes other issues. Or piston clearance issue.

  15. The numbers you stated are in the general ballpark. What was the failure mode causing you to be towed? What do the bearings look like? What were the ring gaps set at? Picture are usually helpful. Chuck

    G'day Chuck

     

    Sorry no pictures yet as block etc at the machine shop 50 miles away

     

    Story in short I was driving along the highway 50-60 MPH all going well and constantly checking the gauges

    Heard a noise like loose tappets then looked at the gauges, oil pressure 40 and slowly dropping

    Had to drive a couple of miles, very slowly, to find a parking bay and shut down, checked for leaks, none, checked oil, clean as a whistle and full, so clean I had trouble seeing the oil on the dipstick. Checked it several times, same.

    Got vehicle home and perhaps from getting on/off the tilt tray the oil had mixed so it was now a dark color on the dipstick

     

    What I'm having trouble comprehending is that if the bearing clearances were too tight there should have been some wear from the beginning and there would have been some discoloration in the oil much earlier on especially after the dyno testing

    Ring gaps were set at where they should be but don't quite remember exact measurement, I did file a little too much off a couple but that wouldn't cause any problems

    In my opinion it is more likely an oil starvation issue considering all bearings including thrust surfaces are worn, number 4 cylinder badly scuffed perhaps as one of the last to receive oil

     

    Machinist is yet to examine the oil pump, galleries and camshaft so will have to lose some more sleep waiting

    Luckily the crank can be saved and the block will only need one sleeve at this stage

    Hopefully I have more news in a week or so

  16. Still waiting on my engine's final autopsy and getting different stories/theories every week

    In short I rapidly dropped oil pressure on a fresh 406C stroker resulting in engine noise and a $400 towing bill

    Decided to send it to my machinist a couple of long weeks ago and his initial diagnosis after removing a couple of bearing caps was the thrust bearing was wiped out due to the crankshaft being pushed forwards

    This led to "a" conclusion it must be my transmission having excessive charge pressure or a misalignment issue which is certainly a possibility but the fact there were no witness marks on the flexplate or convertor I was not convinced

    Having excessive pressure in the trans would also cause excessively harsh shifts which was certainly not the case at all

    Regardless I took the trans to a local shop and he can't see any evidence of this so far

     

    Get another call from my machinist to say they have removed the crank/pistons etc and after measuring the wear on the thrust, end play and the fact that all the bearings have prematurely failed/worn he no longer blames the trans but thinks the clearances might have been too tight

    I told him my oil pressure was consistently 80-85 psi cold, 75-80 hot revving with approx 50 psi hot idle which to me is not excessive for a new engine

    I don't remember my exact clearances but checked them with plasti-gauge (I know not perfect!) and they were certainly within spec at about 0.0025-0.0030 mains and 0.0020-0.0025 rods

    The crankshaft turned freely even with pistons installed and although plasti-gauge is not ideal even at the tighter side of the above clearances I am far from convinced it was the clearances causing this failure

    The oil was always clean even when I stopped the vehicle and wasn't until I got home the dirty oil finally mixed in

    Machinist is yet to check oil pump, galleries and cam bearings so could get another story next week

     

    My "theory" is something caused a drop in oil pressure such as a blocked oil gallery or an internal leak such as a slipped cam bearing or oil pump issue which led to the bearing failure and major scuffing in no 4 cylinder with minor scuffing in the rest

     

    Would be interesting to hear from members what oil pressures they have had on a fresh engine especially with new crank, rods etc

    Oh and you're welcome to add to the theory list, I could use a laugh right now

  17. I see you have a rivnut tool also, very handy for some applications

    Reckon you'll have that beast painted soon and glad you've stuck to the original green

    Are you able to paint in your yard/shed or is it a no no in your town?

    I can get away with some minor painting but hired a spray booth to do the big job due to bugs having a liking for 2 pack paint!

     

    As for my vehicle I'm awaiting an autopsy on the C4 trans which should determine the cause of the engine failure

    Will post a full report later but so far the crankshaft thrust bearing has failed due to the crankshaft being pushed forward

    This could be anything from the flex plate backwards but suspect the trans has somehow suddenly increased converter charge pressure and forced the crank forwards

    Just one of those unfortunate things that happens

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