VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 28 engine making weird noise

So I rebuilt a motor i had reconditioned 20 years ago, long story for another thread, put it in my ute drove it for about 2 weeks then started to make a odd hollow clattery sound, first I thought I had done a bearing, but after a full pulldown and check all the big ends looked perfect, as I had only just rebuilt it would have been odd but never assume with 90 year old machinery. Next I set the motor up in my engine stand and ran it, for about 1 min as there is no radiator hook up, it sounds good but as it stops I hear the noise. I took off the timing cover as it seems to come from inside and the noise was louder when I ran it again, an inspection of the teeth shows no wear, chips or missing teeth so I'm perplexed? any ideas folks, Ray

Is the camshaft gear made from steel instead of fiber? For '28, the cam gear should be fiber.

The '27 engine used a steel cam gear and it would fit into a '28 engine. If your engine has a steel crank shaft gear driving a steel camshaft gear, there would be excess noise.

If you fire it up again, I suggest getting one of those engine stethoscopes which will help you pinpoint where the noise is coming from.

Dean

Morning Dean no mate it’s standard configuration fiber gear. I’ll use the wooden dowel to the ear trick and see if it enlightens me any. I took video but not sure how to post it here. Ray

Ivan forward video of engine running if some one else can post it

I don't think you can post a video directly to the VCCA website.

Instead, you can upload it to youtube (it is free to do so) and then post a link here to that video.

Cheers, Dean

Ray, I would check for end play or side play in the camshaft. Maybe the cam retainer plate screws are backing out. Is there any scoring on the inside of the gear cover? I would also check the distributor gear and camshaft worm gear. Good luck.

Try this https://m.facebook.com/home.php#_=_

The link asks me to log in to facebook.

Your link probably works for those who have a facebook account. I do not, nor do I want to create one.

Happily unsocial, Dean ;-)

ahh yes I fully understand that Dean, no the backing plate for the cam was not loose, there is a bit of back lash in the gears but nothing for an engine this old, I have now stripped the engine down to just the crank and pistons still in it, the cam shaft looks fine il will check to see if there is any whip in the cam shaft maybe it is slightly bent? no slop in the pistons and I wouldn't expect any they have only done 2000 miles , Ray

Check the crank bearings. Do not use plastigauge. When I rebuilt my motor with new white metal bearings. it had a knock when reassembled. Plastigauge said 1 1/2 thou clearance on all bearings. An old time mechanic checked bearings with shim steel and had 8 thou on centre bearing. Goes to show modern methods are not always better.

How about your thrust bearing clearance for the crank? My '28 has ~.025" slop (I believe spec is ~0.004") on the center thrust bearing which causes it to rattle a bit depending on engine load and speed. I could fix it by re-babbitting the mains but figure I'll wait until I need to tighten them up again (all the other clearances are within spec but I'm out of shims to pull).

To Steelin_Time's point on Plastigauge, it is easy to get a bad reading with it when using it on Babbitt bearings and the old school ways work great if you know what you're doing. If you do use plastigauge, make sure to liberally oil the bearing and journal surfaces and take the reading on the journal NOT the bearing and take a couple measurements to verify it's correct.

-Tyler

Hi Tyler I’ll look at that hadn’t cross my mind as this motor was reconditioned not that long ago. I’ve also got two slightly bent push rods for no apparent reason valve don’t stick not marks on top of pistons to indicate a foreign body got it . I’m putting that down to fatigue of the rods and will install fresh ones. Ray