Lynx II, hull # 4225

[super dave]

Well Gents I need some input to a problem I came into well setting up Peters engine on my test stand as I am going to run the motor up for a while to make sure there are no problems with it before I ship it out. The problem came when I was going to install belts on the pulleys and noticed that the lower Crank pulley was off quite a bit compared with the water pump pulleys. I removed the lower crank hub pulley to see if I could spot the problem and it wasn't until I compared it with another 2 grove and single grooved pulley that I measured it against that there was 3/8" difference between the other 2 pulleys. Now here is the thing, Peter sent me his water pumps and the lower Crank hub pulley from his engine and he said that it all lined up ?? I installed a single grooved generator and one off a carrier and both lined up with the water pumps. The lower crank hub pulley that is for the Lynx is sort of special as the fan bolts to it not like most of the other setups.

Does anyone have a close picture of a stock Lynx lower crank hub pulley That I could see as I am at wits end trying to figure why its longer than the stock units making it stick out the 3/8" further. I measured the back side of the pulley to the lower timing cover bolt (see pictures) and it comes around .550 but the carrier/CMP double grooved pulley is at .380 which lines up perfect. Also the pulley is fully seated against the lower cam gear.


Help Help Help

[chris vickery]

Longer crank?
Maybe have to have the pulley shaft shortened.

[Lynn Eades]

Does the pulley have a part number?
I'd at least go to the parts book and find out if this is the correct pulley.
The Lynx was probably not the only crank driven fan.
Maybe one of the other Lynx owners has the answer?

[super dave]

The pulleys part number of C 29SR-6312 matches the parts book which Peter sent me. I asked him to send me the measurement of his generator on how far the pulley stands out which seems to line up with the water pumps.

Chris, I already thought of shorting the pulley but the seal surface would not be correct ant then the crank shaft would be sticking out past the pulley so that would not work.

The weird thing is that they all lined up on the engine that came out of Peters lynx and he sent me the water pumps and the lower crank hub pulley from it and I got him to measure the crank snout from the cam gear and it measures the same as the engine I built him

Here is a picture that Pete sent me of his engine.

[David Dunlop]

Is there anything different going on with the front face of the two blocks?

David

[chris vickery]

Maybe David is on to something. Was a different block used or the original one?
Maybe you will need to make spacer shims for the water pumps

[David Dunlop]

Looking back at earlier photos of Dave's engine rebuild, there seems to be a small casting that bolts to the face of the block, bottom dead centre at the front. The pulley assembly then fits over the shaft protruding through this small casting.

Is that casting original to the Lynx engine? If it is, everything should fit. If it is not the original casting, perhaps it is longer and causing the problem. The engine Dave is working on has a constant plane across the face of it, no recesses or protrusions for the water pumps, so if all the right pieces are attached to it, they should all line up. So now I am thinking a rogue part might be the problem.

David