Carrera 3.2 top end rebuild

[preston_brown]

OK John, if I'm reading this right, you're suggesting that I pull off the cam towers and do the rocker/cam assembly on the bench. I'll have to clean up a bunch of sealant I was hoping to avoid and go through that whole torquing procedure again, but you are suggesting it will be the easiest/best way to go? No problem.

Munchovie, I did end up using Yamabond, that sure does look like great stuff.

Also, here's a pic of the P&C's that I got from Henry Schmidt. Thanks Henry, I think these are going to work out well, and after sending my old Alusil cylinders to EBS as cores for them to re-plate, it was a very fair price as well. Ignore the orientation of the P&Cs to each other in the pic; everything is just sitting there post-cleaning.



-- Preston

Originally Posted by john walker's workshop

finish installing the cam and all the rockers and shafts first, them install them as an assembled unit. turn the cams so the keyways face straight up and set #1 and #4 pistons to TDC before joining things up. then you can hang the sprockets, chains and tensioners, slip in the timing pins, snug the cam bolts and then it's ready to set the cam timing.

[john walker's workshop]

not quite. don't take the cam towers off the heads. just continue assembling them completely on the bench, (cams, rockers, shafts), then install the complete assembled unit (cam towers, heads, cams, rockers, shafts) onto the engine. easier that way.

[preston_brown]

Got it, and that makes more sense. Thanks.

Making some pretty good progress for a change tonight, update in awhile, hopefully no issues to report.

[preston_brown]

Almost ready for timing, more progress this weekend than in about two months.

[efhughes3]

Sounds like you've learned well, my youn Jedi.

[preston_brown]

Originally Posted by efhughes3

Sounds like you've learned well, my youn Jedi.

We'll see if the timing goes any quicker/easier than it was for you Ed. Maybe use the tip I read last night to keep the cams just slightly rotated left of having the 930 at the absolute top. Then I can use the cam bolts to rotate them clockwise. I've gotta wait until Thursday -- that's when I'll have a cam holding bar. I'll probably try to do some other projects until then like reassembling the fuel injection system and getting that ready.

[efhughes3]

What you'll need, I think, is a bolt the same thread size as the cam bolt, but longer. That would let you bottom it out in the cam's threaded hole, and be able to turn the cam without touching the sprocket, if I understand what some have done. This will allow you to adjust the sprocket as needed and pin it without interference from the cam bolt. When it's tightened down, it conceals some of the pin holes.

[MBEngineering]

HI preston_brown
try this for your cam timing, it may help?

Setting cam timing with bolt-snout cams

regards mike

[efhughes3]

Originally Posted by MBEngineering

HI preston_brown
try this for your cam timing, it may help?

Setting cam timing with bolt-snout cams

regards mike

Mike, that method wouldn't work on mine, the cams would not stay put. That is why an extra long bolt bottomed out would allow one to hold the steady while still being able to drop the pin in.

[MBEngineering]

HI efhughes3
if you put the intake AND the exhaust rockers in the cam box for the same cylinder,(No'1 & 4 cylinders) I am afraid it will work !!. if you just put the intake rocker in and no other rockers, to set the cam timing it WILL NOT WORK.

regards mike

[preston_brown]

Originally Posted by MBEngineering

HI efhughes3
if you put the intake AND the exhaust rockers in the cam box for the same cylinder,(No'1 & 4 cylinders) I am afraid it will work !!. if you just put the intake rocker in and no other rockers, to set the cam timing it WILL NOT WORK.

regards mike

I got the timing done without much trouble. I was able to have the cam stay in place without any rotation issues with both intake and exhaust rockers installed. Simply set 930 mark up, rotated crank from TDC until I had the correct overlap, pulled the pin, rotated the crank a little bit more to TDC, reinserted the pin, tightened up the bolt, rotate 720 degrees a couple of times to check, and either success, or pulled the pin and rotated the crank a little bit to adjust. It would have been more difficult, I assume, with a higher lift cam.

I initially was using Stomski mechanical chain tensioners, but I think I had a bit too much tension on them while doing the timing, as after swapping them out for my carrera pressure-fed units, overlap increased by .07-.10mm. So, I had to re-do it with the carrera ones installed. Anyone want a pair of Stomski chain tensioners?

I got the left side set to 1.21-1.23mm, and the right to 1.18-1.20mm, repeatably. Going to the "next sprocket hole" got me uncomfortably close to the high limit on the left side, so even though I know ideally both sides would be at 1.26mm (964 profile cams), this is how it worked out. My arm did sure get a workout from repeatedly torquing and untorquing the cam bolts during the process.

Got the rest of the valve train installed and everything set to .004" gap. So nice to set the valve gaps with the engine removed! A piece of cake compared to doing it in the car.

Chain covers went on last night and I started installing the oil lines. I have to reassemble the fuel injection puzzle but I'm getting very close now! Obligatory progress picture attached, sorry for the quality. It came off an iPhone.

[efhughes3]

If you haven't considered it yet, replace your crank sensors and high pressure fuel lines as part of your final assembly.

[preston_brown]

I am doing the crank sensors and the cylinder head temp sensor. The insulation on mine totally peeled off when I removed them.

I will get new fuel lines, the old ones have been sitting around for 10 months now and maybe they are now leaky.

[preston_brown]

Wow, that fuel line isn't cheap! Currently $373 from Pelican.

Any good ideas on methods to pressure test my current one? I'd rather not change parts just for the sake of changing them if mine hasn't developed a leak. It was fine back in March...

[preston_brown]

Well I inspected the fuel line and it *looks* good but I know that isn't a really effective way of evaluating it.

Unfortunately, this vacuum (?) line has a crack in the rubber part:



It is here:

http://www.pelicanparts.com/PartsLookup/HTML/911_USA_87_89_KATALOG/107-00-Frame3.htm

Part #24 coming off the plastic "snail" hooked up to the air flow box.

Can I try to repair the crack with some Goop and plumber's tape? I am under the belief that all this line carries is air. The replacement is $140!!! Crap.

[efhughes3]

Originally Posted by preston_brown

Well I inspected the fuel line and it *looks* good but I know that isn't a really effective way of evaluating it.

I knew that would be your answer. Well, I did the same thing 2 weeks ago. A buddy had even asked me about them, and I had the answer that "they looked fine and never leaked before, everything will be OK".

Well upon the first pressurization of the fuel line, it leaked at all three clamp locations. End of my first attempt to fire her up, glad it didn't get any worse. It's a lot easier putting your new line on while the engine is out.

The sensors? When I plugged the car's harness into them, the plugs on both of them crumbled partially. I figured why take the chance, so those were replaced too. The CHT had already been replaced as a 2 wire unit.

[john walker's workshop]

that line with the yellow caps in the picture can be saved by slipping a short length of heat shrink tubing over it. a heat gun shrinks it down real nice like and seals any vacuum leak. as for the expensive fuel line, if the crimps are tight enough that the rubber hose doesn't turn real easy on the metal tube, and the rubber hoses are not covered in little cracks, i'd reuse it. there are also many hydraulic repair shops that can replace the hoses and crimp sleeves. just be sure they clock in both ends so the fittings point to the fuel rails at the proper angle.

[efhughes3]

I'd go the custom route on the fuel lines and just be done with it. Again, mine looked great and was never an issue prior to my mis-shift. I don't know if the handling in installing it during my build or sitting idle thru the summer dried it out or what, but the experience of delaying the start of my new engine is quite fresh in my mind.

Originally Posted by john walker's workshop

that line with the yellow caps in the picture can be saved by slipping a short length of heat shrink tubing over it. a heat gun shrinks it down real nice like and seals any vacuum leak. as for the expensive fuel line, if the crimps are tight enough that the rubber hose doesn't turn real easy on the metal tube, and the rubber hoses are not covered in little cracks, i'd reuse it. there are also many hydraulic repair shops that can replace the hoses and crimp sleeves. just be sure they clock in both ends so the fittings point to the fuel rails at the proper angle.

[88911coupe]

I've got exactly the same cracked hose pictured above and did not realize it was 140! thanks fot the tip John.

[preston_brown]

John,

Great tip on saving vacuum lines with heat shrink. I've got lots of various sizes of that in my cabinet, so that is a go. I'll evaluate the condition of the fuel line more thoroughly (i.e. check for any spinning of the rubber inside the crimps), but there are no cracks or crazing.

Got most of the FI/intake manifold setup reassembled tonight, and ready to sit down on the rest of the engine.