Need Mac ID Info

[Dennis Detweiler]

Steve,
Bearing, sidecover and crank stayed together when dismantled. I visually checked with a flashlight into all corners of the block, stuffer, piston, etc, for the needle and couldn't locate it.
Flywheel has a large raised #8 and a small raised #2 on the front. Back of the flywheel has an "H" on the casting circles.
Top of cylinder has (felt marking pen) 91b1, 2.191, +20.
At TDC I can lay a quarter on top of the piston and it is flush with the cylinder top (more than .015).
My mic is a smaller 1 inch. I'll have to invest in a couple of mics to get cylinder and piston size. Lower piston ring is compressed and not free on the piston.
Thanks,
Dennis

[steveohara]

Dennis,

If the bore is the size shown it is .025 over. A .020 over piston will measure 2.180" at the skirt and that would give the motor .011 clearance which is way too much. The 91 should be set up with .006 to .0075 clearance with a new piston. From your description of the deck height measurement it sound like you have what is called a "quick time" piston and you'll want to replace it with a standard type to get the deck clearance and compression where they should be. If the piston you have is not damaged and you remove the rod carefully you can probably sell it for a good price as the "quick time" pistons are very scarce.
Rather than purchasing additional micrometers I would recommend a digital caliper. You can pick them up on ebay or buy from Harbor Freight onlilne for less than $30. It will be a much more useful tool as it will handle ID, OD and depth measurements.
There should be a "5" stamped on the top of one of the raised posts near the center of your flywheel... if you can't find it you have a "standard" flywheel rather than the correct "5 degree" flywheel.
Looking forward to seeing the pictures.
Regards,
Steve O'Hara

[Ronald Cubel]

Steve, They made lots of 5 deg flywheels w/o 5 stamped on them. Vince has got a bunch of new ones if you need them.

P/n 68280

Nedd to check keyway location

Ron

[Dennis Detweiler]

I sent 15 pics through comcast address yesterday. Evidently, that won't work. I'm not sure how to post directly to this page? I have webtv. Maybe not compatable? I may have to send pics to your email address. Or, a work or personal website address. Or, someone else can post them if I can forward to their address. Steve, I also sent an email to your posted email address a few days ago, but it must not have reached you. I reposted the info on this thread yesterday.
I'll try to post those pics again tonight.
Thanks again for everyone's help.
Dennis

[steveohara]

Ron,

I have never seen an OEM 5 degree flywheel that came on an engine that was not marked. Perhaps there was a production run of replacement parts that found their way out there without the markings?? I have checked flywheels with the raised "2" on them that some folks think are 2 degree flywheels but they all check out to be the same a standard flywheels.
Hopefully the pictures Dennis takes will allow me to see the key position.
Regards,
Steve O'Hara

[steveohara]

Dennis,

I use the Image Shack service to post pictures. The service is free and it is easy to link the pics to forums like this one... http://www.imageshack.us/
If you want to send pics directly via email you can use steveohara@msn.com as the email address
Regards,
Steve O'Hara

[Ronald Cubel]

Steve, Sorry but there are lots of them, mostly newer production so check them befor you throw the away. Ron

[steveohara]

Ron,

I have 11 unmarked flywheels here and all of them have been checked on my fixture and they are all std timing. If I get any others I'll be sure to check them.
Thanks for the heads up!
Steve

[John Tzortzoudakis]

Steve,

When you said in your earlier post "the correct intake manifold should have an "H" on it near the exhaust"
What does the H for? I once heard it means Horstman for the later engines that were ordered by Horstman.; I think all mc93's were ordered by Horstman and distributed by him. I can't see a difference between manifolds with or without the H but what does the H mean? What engine did they belong to? Any thoughts are welcome.


thx John T