[bladeracer]

Originally Posted by D.S

Worked with it the whole night, it took 4 more hours than I expected but I finally got it right.. I found it difficult to align the camshaft sprockets because they don't rest flat on their guides before the camshaft holders are tightened, and they kept being off by a tiny bit when tightened even if they looked right before. When I finally got them right the timing sprocket wasn't aligned anymore for some reason and it took me a while to move the chain a tooth at a time, turn the engine, move tooth, turn engine etc until it also aligned. What annoyed me was that there was no mark to check the timing without placing the clutch cover in place every time..


I did eventually screw up big time while torquing one of the outside two smaller screws of the head against the crankcase (marked on the attached pic).. I set my P.O.S. torque tool to 24nm like stated on the manual but instead of the expected "click" sound I got a "snap" sound and I think I used up all my vocabulary of profane words.. All inside screws around the cylinders torqued fine at 51nm. Don't know if it's the fault of the inaccurate tool at lower torque settings or if I shouldn't have lubed the screw thread/head. The haynes manual said to lube them so I did..

It snapped between the head and crankcase and one should be able to get it out without having to pull the head again. It's just something I won't do myself, the potential of messing up the crankcase is huge I guess.. Another less thought-out idea was to testrun the engine and hope the head will stay tight. It's the part of the engine with the camchain so maybe not so critical for the integrity of the cylinders/head gasket? I would fix it properly during off-season.

Turn the crank clockwise to bring #1 piston to the top and align the timing mark on the pulse rotor and then turn it back so all the pistons are halfway down the bores and then lay the cams on. Tighten the cam holders down progressively but you don't need to worry about their positions yet. You did liberally oil the cam journals and buckets first?
Now turn the cams so the timing marks align with the top surface of the head and point outwards (usually but I can confirm if you don't have a manual). If the sprockets have markings for both IN and EX be sure they are correct - IN is the rear cam near the carbs and EX is the front cam near the exhaust header pipes. If #1 is on the compression stroke then both valves should be closed with both cam lobes pointing away from the valve buckets. Now slowly turn the crank clockwise just enough to bring it back onto the timing mark - I always confirm the piston is at TDC with a screwdriver down the plug hole.
Now install the tensioner with the ratchet locked back.
Now check that the camchain is correctly around the crank sprocket and pull it tight up the front of the engine and around the exhaust sprocket. Keeping it taut wrap it around the intake sprocket and keep pressing it onto the sprocket as you release the tensioner lock to ensure it doesn't skip when it comes under tension. If you have a manual tensioner, tension the chain now.

If you have a white paint marker put a dot on the camchain pin adjacent to the timing marks on the pulse rotor and cam sprockets for easy visual reference.
Now _slowly_ turn the motor clockwise a few rotations to squeeze any oil out of the cam buckets and ensure the valves aren't hitting any pistons. If you feel any resistance, stop immediately and poke a screwdriver down the plug holes to confirm that no pistons are at the top of the stroke while either of their valves are open.
If you remembered to check your valve clearances before removing the cams you would've already replaced any shims needing adjustment, so now you just need to check the clearances. If not, then you'll need to remove the cams again if any clearances are out of spec and do it all again.

With blind holes you must blow them out with air first to ensure there's nothing in there or the bolt will be torquing down on that obstruction or oil instead of the flange of the head. The broken bolt should come out fairly easily as long as it hasn't been loktited as, once the head is broken off there's no load on the threads anymore. I would recommend removing the head first but it may not be essential. With the head off you might find the bolt has broken high enough up the shank that you can grip it with pliers and avoid drilling.

[D.S]

Originally Posted by bladeracer

Turn the crank clockwise to bring #1 piston to the top and align the timing mark on the pulse rotor and then turn it back so all the pistons are halfway down the bores and then lay the cams on. Tighten the cam holders down progressively but you don't need to worry about their positions yet. You did liberally oil the cam journals and buckets first?

I used a mix of moybdenium(spelling?) grease and engine oil. Not too much, heard it could be bad if too much of it got flushed into the transmission

Originally Posted by bladeracer

If you remembered to check your valve clearances before removing the cams you would've already replaced any shims needing adjustment, so now you just need to check the clearances. If not, then you'll need to remove the cams again if any clearances are out of spec and do it all again.

Planned to do that tonight but want to have an opinion on what to do about the screw. Use the engine like that for a few months or tear it up again, spend another week waiting for the shop to fix it, get new $70 head gasket.. its a hassle I'd rather postpone to off-season. What damage other than a bad head gasket and some oil leakage could there be from running the engine like this? The gasket I have to replace regardless..

Originally Posted by bladeracer

The broken bolt should come out fairly easily as long as it hasn't been loktited as, once the head is broken off there's no load on the threads anymore.

No locktite, only grease/oil on the threads.. How about carefully drilling a little into the screw and then slowly back the drill in reverse?

[bladeracer]

Originally Posted by D.S

I used a mix of moybdenium(spelling?) grease and engine oil. Not too much, heard it could be bad if too much of it got flushed into the transmission



Planned to do that tonight but want to have an opinion on what to do about the screw. Use the engine like that for a few months or tear it up again, spend another week waiting for the shop to fix it, get new $70 head gasket.. its a hassle I'd rather postpone to off-season. What damage other than a bad head gasket and some oil leakage could there be from running the engine like this? The gasket I have to replace regardless..



No locktite, only grease/oil on the threads.. How about carefully drilling a little into the screw and then slowly back the drill in reverse?

The moly grease and oil mix is good. If I'm building an engine I don't expect to have running soon I prefer to use an assembly lube.
You haven't run the engine yet so the head gasket should be fine.
I don't think those two M8 bolts do much but there's an engine mount immediately above them so it's possible they are there to take some frame loads. I'd fix it now while you have the engine out.
If you can get to the broken bolt with a centre punch and drill a hole into it then get a screw extractor and screw it out that way. Sort of like a reverse-threaded screw with sharp threads that cut into the metal of the bolt.

I had to get an engine cover bolt out of an engine two weeks ago by welding a rod to the bolt head. Worked fine but you've got to be very careful you don't melt the engine :-) The melting point of aluminium is just a third of the heat you're using to weld the steel bolt.

[D.S]

What is this "center punch", is it a guide for the drill to make sure I go in straight? And is that screw aluminium? Can't check atm..

[bladeracer]

Originally Posted by D.S

What is this "center punch", is it a guide for the drill to make sure I go in straight? And is that screw aluminium? Can't check atm..

A centre punch will punch a tiny hole to keep your drill bit centred. Without it you'll be drilling more out of the head than the bolt. You _must_ punch it first.
No standard screws or bolts are aluminium and certainly not anything that takes even slight amounts of torque.
The bolt will be steel.

[skorpia]

the bolts holding the cams down should be replaced...from what ive learned over the years - and busting too many of the damn things - that they are really only made for one good torque down. anymorwe then that and you wind up with a busted bolt

[D.S]

I replaced both exterior bolts, the inside bolts survived the retorque so I'm keeping them there. But it makes sense to replace them and I'll have it in mind next time the head comes off for whatever reason.

[Bad Karma]

Originally Posted by Jetpilot07

wow, i was looking for porn!!!!

Only reason I clicked on it man....sorry for no help.

LMAO,
Ivan