2F Engine Knock (1 Viewer)

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First thing that came to mind after the misdiagnosed #1 and #2 cylinder knock is likely a bad timing gear. The rubber insulation within the gear is shot.
 
Mine did the same thing.I took it to a few places to diagnose.Someone said it was a rod knock and someone said it was a wristpin. It was to high to be the bottom end.I rebuilt it and now it dosen't make that sound.LOL
 
Mine did the same thing.I took it to a few places to diagnose.Someone said it was a rod knock and someone said it was a wristpin. It was to high to be the bottom end.I rebuilt it and now it dosen't make that sound.LOL

HAHAHA! When all else fails, go overboard!
 
When you had the conrod bearing caps off could you feel any excess movement in the gudgeon pin [conrod to piston connection, not sure what you blokes call it]?Did you check for this on all cylinders? cheers


I did not feel any excess play in the wrist pins when connecting rod bearing caps were off.


First thing that came to mind after the misdiagnosed #1 and #2 cylinder knock is likely a bad timing gear. The rubber insulation within the gear is shot.


My next free weekend I will take a look at the timing gears. That will give me a chance to inspect the cam, lifters, and pushrods while I'm at it. I am getting a crash course in 2F internals, good thing I slept at a Holiday Inn Express last night.

A few addtional questions:

I've read differing opinions on this board about replacing the cam gear w/ either an OEM gear with rubber insulator, or a solid aftermarket gear w/o the insulator. Does anybody have any strong opinions on this matter? I don't see a good reason not to go OEM unless they are a weak point of the 2F (or ridiculously expensive).

After removing the pushrods and lifters, do I need to worry about anything falling down into the oil pan when removing the camshaft? I don't really want to pull the pan again unless I absolutely have to.

I really appreciate all the advice, I feel like I'm getting close to the source of the knock.
 
UPDATE: Camshaft Thrust Clearance

After many months of enduring my engine knock, I finally tore into the front end this week. To my delight, I found that the cam thrust clearance is a whopping 0.032 inches (nearly 3 times the limit in the FSM). I am assuming that this is the source of my knock, considering that the crank pulley, timing gears, cam lobes/bearngs, lifters, and pushrods all look fine. I'll try to track down a new thrust plate tomorrow. Incidently, it looks like the camshaft timing gear was replace by a previous owner because it is a "solid" gear w/o the rubber dampener.

Soooo....it looks like Pin_Head had this one nailed with his post back in February. I'll re-post when I get her put back together again to hopefully report a smooth, knock-less motor.
 
it looks like the camshaft timing gear was replace by a previous owner because it is a "solid" gear w/o the rubber dampener.

are you planning on replacing the punk-ass solid gear w/ the dampened one? :confused:
 
Just an update to bring some closure to this thread for future readers. I replaced both timing gears and had both the camshaft and lifters re-ground. Last night I fired it up and the knock is gone! Ultimately, I believe the knock was a result of excessive camshaft end-play and worn gears (too much backlash). As a bonus, I'm getting noticeably better performance from the re-ground cam profile (250S from Delta Cam) and my timing plate oil leak is fixed.
 

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