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brsvo
05-23-2014, 09:20 AM
When I start my 84 every now and then it will go knock-knock and then it sounds fine? Only hear it when it first fires not after. Why would it do that? 2 years ago I had a M127 pump put in so it shouldn't be that.
MikeFleming
05-23-2014, 09:59 AM
Is the knock actually a tapping? High or low in the engine? Worse (louder) with load or same?

Oil pumps do not solve leaky lash adjusters (top of engine) or rod bearing clearances (bottom of engine).
brsvo
05-23-2014, 10:48 AM
Heavy clank sound not a lite tapping and it is very slow and distinct. I am in the car at the time so I have to get help to say high or low! But it just started doing this recently. I always though of rods going in a blaze of glory at red line not at start up!
MikeFleming
05-23-2014, 11:29 AM
Best stop running it then - to limit the damage. Send some of the crankcase oil off for analysis to see how much precious metal is in it..
BLK BRD 88
05-23-2014, 04:22 PM
When I start my 84 every now and then it will go knock-knock and then it sounds fine? Only hear it when it first fires not after. Why would it do that? 2 years ago I had a M127 pump put in so it shouldn't be that.
My 84 SVO & one of the 88TCs does something like this. It sounds like it is in the upper front area and it clatters like crazy for about a minute on cold starts.
Is it possible for the timing chain to slap against anything when cold, then stop as the engine warms up?
It can sit for hours after the cold start & has no sign of the clatter when restarted.
Ron
brsvo
05-23-2014, 09:30 PM
Timing belts ( rubber) shouldn't make metallic sounds?? I will look into getting the oil analyzed-any suggestions where I would send the sample?
BLK BRD 88
05-30-2014, 08:56 PM
Timing belts ( rubber) shouldn't make metallic sounds?? I will look into getting the oil analyzed-any suggestions where I would send the sample?

That shows how much I know (don't know) about these 2.3 engines.
Ron
svono50
06-02-2014, 07:09 PM
Bruce, I would suggest using Blackstone Labs, they have free 'kits' for packaging up your oil and sending it back to them, very easy to use and pretty quick results.

http://www.blackstone-labs.com/