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goose2
OK...I'm doing my first valve adjust on a 914-6 conversion. I've done 911's before, so I know the basic procedure. What I'm wondering is....how do you see the timing marks on the pully? I know there are other ways to find TDC and the 120 degree increments of rotation. Seems I recall hearing about a trick using a chopstick here too laugh.gif Do I need to resort to voodoo and piston telepathy?
Thanks
ArtechnikA
well - there are two right answers. the "most" right is: flashlight and mirror; the pulley has the 120* marks. the 'smart' person will transfer the #2 and #3 marks to the flywheel where they can be seen along with the standard timing mark.

of course, the 'easy' answer is to use Cap'n Krusty's valve adjustment method, which works as well on /6's as it does for /4's (although for different reasons).
Dr Evil
QUOTE (ArtechnikA @ Jun 25 2005, 12:54 PM)
of course, the 'easy' answer is to use Cap'n Krusty's valve adjustment method, which works as well on /6's as it does for /4's (although for different reasons).

link please biggrin.gif
ArtechnikA
Link Provided for the 3rd or 4th time this month, for the search-impaired :-)
goose2
I'm familiar with Capn's method on a 4 cyl, but not sure I trust it on a six...2 cams operating off rockers instead of one with lifters opposite each other changes the theory considerably. Also, I don't think I would trust my ability to interpolate the 4 table to use on a six. This is NOT a fun job and I don't want to do it again soon.....guess I'll do the flashlight and mirror dance this time.
Thanks for the info............
Cap'n Krusty
Bump the motor over until a rocker is fully rocked open. Adjust the opposite valve. Simple, clean, and easy. BE SURE to leave the spark plugs in while you do this. 2 reasons: (1) the engine will over run every one(!), and (2) you run the risk of carbon dropping into the exhaust valve opening and making your adjustment waaaaaaaay off. The latter is true for any method you use on a 911 engine that has been run. The Cap'n
goose2
Ah...the Capt'n speaks...was hoping you'd chime in on this. By opposite valve, you mean same valve on opposite cyl? For example: adjust #4 intake while #1 intake fully open? Dumb question maybe but I want to get this right.
Thanks
Jeffs9146
QUOTE
how do you see the timing marks on the pully?


Seems to me there is a timing mark on the flywheel also! You should be able to see it from the top rear of the motor or the bottom of the trans.

Jeff
goose2
I couldn't see any mark on the flywheel (underneath) at tdc...so i drilled a tiny holt there and filled it with orange paint. There's no opening to the flywheel on top. I'll do the same at the 2 120degree points as well........If I ever find them. headbang.gif
ArtechnikA
QUOTE (goose2 @ Jun 25 2005, 05:59 PM)
I couldn't see any mark on the flywheel (underneath) at tdc...

There's no opening to the flywheel on top. I'll do the same at the 2 120degree points as well...

there was never an "opposite TDC" mark for use on the bottom of the engine.
there were no 120* marks on the flywheel - only timing marks, and only on a 914.6 flywheel -- or a 911 flywheel that someone familiar with 914/6's marked when s/he had the chance before the two were mated.

there was an opening in the top of the bellhousing on the 914.6 transaxle; i don't know if it was present on a 914/4 transaxle. with no bellhousing opening and no flywheel marks it must be quite a challenge to time the engine !

do you have a 915 in that car, or did you continue to use a 914 transmission? is it a /4 or a .6 transaxle ?

QUOTE
By opposite valve, you mean same valve on opposite cyl?


same cylinder, other valve. no matter the overlap on the cam, both valves are only ever open at the same time around TDC. if one valve is FULLY open, the other valve MUST be fully closed. it's true that there are times that both valves are fully closed - TDC compression/power stroke - and that's when the factory procedure wants you to measure both valves at the same time.

which works, but there's a lot of moving and checking. so far, it's the method i've been using - but the checking part is easier in a 911. now that i'm comfortable with the 'official', i may use the quicker method from now on...
goose2
Rich....914-4 transmission, no hole in the top sad.gif I've got one bank done using the "easy" method. I double checked #1 using the TDC method and found it very close to the "opposite valve open" method, within .001...and on the safe (loose) side. So I guess the method checks out ok. If it wasn't so damn crowded under there, I'd rig up my dial indicator to check myself. ADVICE TO SIX CONVERSION BUILDERS: adjust valves before installation if you can, and please put TDC, 120* and 240* timing marks on the underside of the flywheel.
mskala
I have the 120 degree marks as well as the 35 degree
mark.

My -6 has plenty of records, but doesn't show the flywheel
ever being changed.

Of course this is not going to help if there is no notch to
look at it smile.gif
goose2
Update...got all the valves adjusted. .....some were a little tight, some a little loose. About half way through I realized with a little rubbernecking and a good light you can SEE when the rocker is on the heel of the cam quite nicely. We don't need no stinkin' timing marks! Thanks for all the good advice though folks....I'm learning so much here!

BAD news...When I took the gaskets I ordered from Pelican out of the bag I saw that two of them were broken mad.gif Some bonehead in the shipping/packing dept. had folded them in half to get them in the box and then jammed my other parts in the order on top. So now I'm ready to reassemble and go for a ride, but it's Sunday and there's nowhere to get replacements here. The broken gaskets are for the top covers but the break is on the lower mating surface. Do you think I could get away with using these for a few days until I get replacements?
goose2
Oh...got my valve covers all spiffed too. The original magnesium lowers were hardly leaking at all so I'm going to reuse them (after resurfacing them)...any recomendations on torque? I think the factory spec is 8lbs but that seems pretty light.
ArtechnikA
QUOTE (goose2 @ Jun 26 2005, 03:57 PM)
...I realized with a little rubbernecking and a good light you can SEE when the rocker is on the heel of the cam quite nicely. We don't need no stinkin' timing marks!

exactly!

i wouldn't trust those gaskets unless you're looking to rust-proof your heat exchangers...

QUOTE
any recomendations on torque? I think the factory spec is 8lbs but that seems pretty light.
and this is the source of leaks and warped covers.

light, even clamping pressure is all you need.
TimT
My car has a 3.2/6 and a regeared/refreshed 914/4 trans

this is what I see when I time the car, a nice opening on the top of the tranny case



goose2
Thanks for the pic, Tim. After taking a closer look I see that my engine tin is a little skewed and overlapping there. I'll have to refit that part and maybe I will find an opening. That would be nice as I don't relish the idea of crawling under the car with a strobe at 3500RPM while sombody twists the distributor to set the timing. If there's no hole, why couldn't I drill 3/8-1/2 inch hole in the trans housing and then mark the flywheel?
Cap'n Krusty
QUOTE (goose2 @ Jun 25 2005, 01:48 PM)
Ah...the Capt'n speaks...was hoping you'd chime in on this. By opposite valve, you mean same valve on opposite cyl? For example: adjust #4 intake while #1 intake fully open? Dumb question maybe but I want to get this right.
Thanks

Yup. I just do all the exhaust valves, button up the bottom, then do all the intake valves. When I'm done, I replace all the spark plugs and button up the top. The Cap'n
Cap'n Krusty
QUOTE (goose2 @ Jun 26 2005, 01:10 PM)
Thanks for the pic, Tim. After taking a closer look I see that my engine tin is a little skewed and overlapping there. I'll have to refit that part and maybe I will find an opening. That would be nice as I don't relish the idea of crawling under the car with a strobe at 3500RPM while sombody twists the distributor to set the timing. If there's no hole, why couldn't I drill 3/8-1/2 inch hole in the trans housing and then mark the flywheel?

3500 RPM? Its a 911, fer cryin' outloud! You time it 6K!
Unless it's a 906 motor, then it's a LOT higher than that.
On the visual determination: You watch one valve open completely, then do the opposite valve. You don't need to watch for the heel of the cam. The Cap'n
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