Derek's 308 engine rebuild

Score yesterday was: sill hoses 2, Derek 0 (-5 if you count cut hands and commiseratory beers consumed.) I thought it would be relatively easy given all the reading, prep work and grease involved. My smooth aircraft cable, well lubed hose and easy access (engine and tank out) should have made it a 10 minute job. My extra pair of hands couldn't make it so I wasted a couple of hours trying to get the silicone heater hose through. I was trying to feed it through from the back and could not get it more than 6-8" up into the passage.

I got out my borescope/snake cam and could see there is a sharp steel plate near the back and the hoses go up, over, and then down into the sill. I found a nice conical steel cap to put on the front of the hose to help guide it through (a nozzle from my daughter's cake icing decorating set.) I will try again on Monday with some help as I think it needs a little push from the back, pull from the front etc.

The guy I got the 1/2" vacuum hose from (Malmberg truck) says he can make up the oil cooler lines and he has the braided stainless hose, lots of Aeroquip fittings and adapters etc. I'll keep you posted as he seemed very competent and clearly relished working on something a bit more exciting than the usual industrial hydraulics.

I also found a good place to rebuild my clutch. Frank at Ottawa Clutch says he does a lot of racing and sports car stuff and he has had good results with the Tribco kevlar which is what a few US vendors recommended on Fchat use. Interestingly, he was also half the price of the two US vendors I contacted (to grind the flywheel and PP and rebuild the disk with Tribco kevlar.)
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Thanks Simon, I must have looked at that oval hole a hundred times while sitting in the engine bay huffing, puffing, and swearing. I feel a bit silly that I didn't think of it as I'm all for improving where I can. I will give it one more try with a friend on Monday as I already have it ready to go.

 

Done! You really need a second pair of hands pulling gently from the front so that as I pushed the hose up and over the plate which was 6" into the passage from the back, the little tugs from the front got the hose to bend down after the plate and start to feed through. Both hoses were in after about 20 minutes of gentle pushing and pulling. If you pull too hard it catches on the plate and gets stuck.

 

Thanks sfm6s, good tip for anyone racing and/or wanting a lighter valvetrain. I might do the switch one day but Cat cams says I'm fine with the original buckets/shims with my cams.

I have been cleaning up the engine bay now that the weather is warmer. I'll do some brush touch-ups with POR15 on the scratches/chips on the frame and then spray with a flat chassis black. I'm hoping the paint shop can read the colour from a few fingernail sized chunks I scraped off and mix me a tin.

I have taken off the oil/emissions plates on the top/sides of the engine bay (I drilled out the rivets) and chiseled/sanded off all the weld splatter in those areas. Some purists may prefer to keep the original weld splatter but I'd rather not.

I pulled a fist-full of grey softish putty out of the back top corners of the engine bay-- looks and smells like old linseed oil window putty. Does anyone know how I can clean it all off safely? Maybe paraffin? The paint on top of it was cracking in a few places so I want to use a more modern filler/sealer I can spray the new paint onto.

I'm heading to Ogdensburg tomorrow to pick up a few things including the ARP rod bolts so should start the final engine build later next week after the rods are resized with the new bolts. Working on a transmission ring nut tool as I want to check the cones and synchros properly while the gearbox is out. I might have found an additional source for the 1st-3rd synchros.
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I figured out with a little testing that the Gunk degreaser works well at dissolving the old grey putty. It takes a bit of time and brushing with a stiff brush, wait, rinse repeat...

While I had the spare wheel liner out I reinforced all the screw holes (on the back) as some of them were showing signs of their age and perhaps some past over-tightening (star cracks and some holes bigger than others.) I scuffed them all and then used some Loctite urethane adhesive and woven glass fibre to patch/reinforce them. This Loctite 3364 has been brilliant at fixing plastic parts (friend's cracked bumper, plastic door handle etc.) You have to be well prepared and only work with whatever you can do in 30-40 seconds. Mix fast for 5-6 seconds, smear on scuffed surface, press on patch, smear on adhesive to cover. You can form it for a minute and it does expand a bit as it cures.

I picked up a bunch of parts in Ogdensburg yesterday and will put the new ARP rod bolts into the rods today and take them for re-sizing tomorrow. I also got my meter of Gates green stripe water hose. More than I need so if anyone else is changing all their old coolant hoses send me a PM.
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I put in the ARP rod bolts. Some have suggested they are much tighter than the originals but I found them about the same. They are so well made they got me quite excited (perhaps a reflection of how exciting my life is

I picked up a Chevy hi-torque PMGR mini starter for $60 and will get a steel adapter plate made. Let me know if you want one-- likely to be under $50. More torque plus easier and far cheaper to change in the future.
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The rods were all .0005-.001" out of round with the new ARP rod bolts torqued so they are being re-sized and they will also hone my small ends to a .0005" clearance. I reamed them to get the pins in but a small clearance is needed for oil.

Baking hot here the last couple of days so doing a few small indoor jobs like cleaning small parts, cutting new hoses to size, making an adapter bracket for my PMGR mini starter, and finishing my gearbox ring nut tool. I will continue the engine bay prep and painting later this week once it is cooler.

 

I finished my ring nut tool and tried the first nut (the left hand threaded nut on the lay shaft near 2nd gear.) After tapping open the locked indents it was so loose it took almost no force to get it loose (supposed to be 20 kgm (144 lbft.)

Two questions, what is the best way to lock the lay shaft for loosening and tightening the ring nuts? I put some long bolts through the drive-shaft flange holes and rotated until they pressed on the case (used some wood pieces to stop scratches.) Is there an easier way? I was concerned about putting a cloth between the teeth of the gears at the input shaft as they are only supported one side and I don't want to risk bending anything.

Second question, any tricks to removing the gearbox oil pump on the other side? I removed the nuts and washers, gave it a wiggle but it feels like something is in the way (speedo drive/sensor?)

The 1st-3rd synchros I found are a copper alloy. Has anyone tried copper alloy synchros? My originals look like some iron alloy and I heard from Brian that those are the only ones fitted by Ferrari. I would prefer the synchros to wear rather than the cones on the hubs.

 

Dave, I think there is enough good info in that thread and the concern about the sulphur content in GL5 harming brass synchros is worth keeping in mind as many gearboxes may have these brass ZF rings. They have the same part number (1249304278) and were used in several European 4x4 transfer cases.

I actually prefer the idea of the synchro ring taking the brunt of the wear and not sharing the wear with the hub (which is more expensive.) Does anyone have any experience with the brass synchros?

 

I found the Daviddriver thread (http://www.ferrarichat.com/forum/308-328-sponsored-yellow-compass-group/112150-syncro-fix-gt4-10314-a-2.html) and saw that the speedo sensor gear might be catching so rotated the layshaft while pulling on the cover-- came off easily. I thought there was an oil pump in there-- not sure where I got that idea. I've read so much and it sometimes gets jumbled.

I got good info from Sean and Verell on the ring nuts (http://www.ferrarichat.com/forum/308-328-sponsored-yellow-compass-group/175114-308-engine-rebuild-cis-twm-throttle-bodies-conversion-thread-13.html) and have added the thread type to my photos.

So my 1st and 3rd synchro gaps were good 0.70+ and my 2nd above the limit (0.4mm) at 0.55mm. I plan to check the cones and see if I can use the 1st ring on 2nd gear and get good clearances on both. I will use engineer's blue to check the mating of the surfaces and buy a new synchro for 2nd if I don't get a good fit.

Does anyone know if thicker synchros were ever made? Since the experts say the cones also wear, perhaps its worth having a few thou extra meat on the synchros and even use brass to reduce the gear cone wear. IN the photos I am pressing the fork to force the synchro ring against the gear cone and the feeler gauge goes between the two sets of dog teeth.
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I finished cutting, drilling and tapping my starter and adapter plate. It is a 6mm steel plate with 5 x M6 countersunk cap screws holding it onto the starter and a steel locating ring that I just need to weld onto the plate.

The starter is a 1.7kW PMGR unit from a Chevy Colorado/ GMC Canyon/ Hummer/ Saab V6 3.7-4.2. They are available from AC Delco, Bosch and a lot of Chinese suppliers. It took a couple of hours to make but I may get a few cut with waterjet if there is any interest.

I got the second ring nut off the layshaft and will take a few pictures later as I mark and remove the shafts and forks.
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I'm not sure if anyone has done a gearbox rebuild DIY but this is what I did. My plan is to replace the 2nd synchro only as all the others are still very good. Ask questions if I have missed something (or got something wrong.)

So for my ring nut tool I used a piece of steel pipe (56mm OD x 50mm ID) and first marked it with 4 equispaced 6mm wide teeth plus a mm of safety margin. I then used an angle grinder with a rough flap wheel to take away about 5-6mm of metal between the teeth. I used a Dremel tool to cut the last mm and checked it a few times on the ring nuts to fine tune the edges of the teeth. I tack welded the piece of pipe to my trusty old drop gear ring nut tool. Or you can buy the 56mm ring nut tool for $100-260.

To lock the shafts, I put an old cotton glove into the 1st gear teeth pair (see photo), pushed the selector fork to engage 1st gear, and used a crappy impact wrench-- not much torque needed if you turn it the right way (see my previous post-- input shaft is RHD thread clutch side, LHD other side, layshaft is opposite, LHD thread clutch side, RHD thread other side.) I didn't take off the long input shaft side ring nut.

Before I started removing all the shift forks and shafts, I marked everything so I can line it up exactly the same later. Since the shafts have machined recesses for the clamp bolts, you can't go too far wrong. Removing the shafts took a bit of tapping here and there and be aware that there are three "Tictac" shaped steel capsules that locate the shafts in their central positions. As each shaft nears the central wall, be ready to catch the capsule as the shaft comes out. I dropped one but it was waiting at the bottom of the case when the gear shafts came out. Note that one of the selector forks (I think 2nd/3rd) has a lock washer (see pic.)

I took out the bearings which came out once I gave the shafts a bit of a push and pull (put them in marked ziplocks so they can go back in the same races.) All of my gears and bearings look very good so far. I gave the two shafts a bit of a wiggle and a few tugs and taps with a rubber mallet and the shafts started to move and eventually came out the clutch side of the case. You have to bear the weight of the shafts as you are tapping to keep them centralised and not hitting on each other or anything else.

I will take apart the layshaft tomorrow and check the synchros and the cones. I was going to pull 1st gear to use that synchro on second but will just put a new synchro on 2nd as even at 280 euros it is still a false economy to use a synchro that has some wear when the gearbox is on the bench in pieces. Mine would probably last another 20-30k miles but a new one should last 2-3 times longer now that the blind hole is drilled (and I'll use better oil.)
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I pulled off the bearing and 4th/5th cluster with a gear puller but you could also tap it off with a soft drift behind the 4th gear on the layshaft cluster. The 2nd gear/cone and synchro slid off nicely and after a quick clean with brake cleaner I made some measurements. The synchro gap is still 0.55mm and the ring "outside" face sits about 1mm inside of the cone edge (see bottom middle photo.)

Brian had suggested that a new ring is about flush with the cone edge so based on Sean's calculations for gap change vs. cone/synchro wear (http://www.ferrarichat.com/forum/308-328-sponsored-yellow-compass-group/315080-interesting-gearbox-wear-part-availability-2.html) it looks like my 2nd cone/synchro has lost about 0.13mm and has about 13% of it's life left. I will get a new synchro ring and measure the gap. If the cone is too far gone I will look for a new cone (perhaps press one off the other applications for this synchro ring-- if I can find one.)
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Just a quick follow up as I realised I could check the 2nd and 3rd synchro rings on each other's cones. The gaps were the same for each ring whichever cone they were on so my 2nd synchro is more worn and the two cones are worn the same (hopefully not much at all.

I have found a good price on the 1249304570 synchro that some have suggested is the same. Does anyone know if there are any differences? Ferrparts has a ...570 on Ebay for $687 claiming they are the same as 106040.

 

I put the new starter into the block+intermediate body and compared it with the original Bosch unit. It is a lot smaller but the solenoid sits higher up so may interfere with the (still clad) exhaust manifold. I'll put the front head on and the manifold to see how it fits. I haven't drilled the 3 holes in the adapter yet so I have about 5-10 degrees of rotation before I have to make another adapter plate (hope not!) The tooth penetration and retraction looks fine but I'll test it with the flywheel once I get it back.
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This morning I took off the diff drive flanges and removed the old cracked seals. There are clear signs of the seal leaking from all the oily grime outside the seal. They are Gaco seals-- not sure if they are original but I will replace them with double lip viton seals-- should last a bit longer. I wouldn't bother removing the diff seal cover as it is easy to seat a new seal correctly with it in place. I took mine off to check the bearings. I used a screwdriver with a bend near the tip to lever off the cover slowly.

There is a bit of play in my left hand output shaft ( the side with the diff seal cover) and I wonder if this is normal? Is my bearing shot?
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