Inter acco 510a 1980

No bigcam original piston had scrape lines but not on top.
Timing has been checked since but makes no difference.

Not much help
YES
the nok should B healed
Other than th@

---

U need sum hi volume 'Dorf Dorfz'





LOL

Cya
[ch9787]

Swishy ... I bin clikin or yer speeker but I carnt get eny noyse outa it!

B Y O noize

inter V8s you do the timing from no 8 cyl ... just thought i throw that in the mix

rose

Learners

Offline



Posts: 6

Inter acco 510a 1980
Yesterday at 23:16:59 Needing advice on engine knock that goes away under load..

Hi Rose,
Do you have an oil light, or guage in the truck.? If only a light, I'd suggest you hook up a capillary type oil guage to check your oil pressure. Starting her up cold she should have oil pressure in at least 2 seconds. If it takes 4 or 5 seconds this will indicate that you probably have worn Big End & Main Bearings. Also, when you turn it off it should take a few seconds before the guage returns to zero. If it goes straight to zero this also indicates worn bearings. Just something to check before going to the trouble of puliing off the sump and pulling out bearings. Little Cab

Rose

You may be in for some grief with that one. I recall a similar thing with a 392 that hd a head job done and came out with a similar knock.

From memory - the piston to valve clearance is very limited - and once the head has been shaved the valves clip the piston. The valves are not adjustable other than to change to a shorter push rod (I think was the deal).

Either way - the one I was involved with took some fixing and was very difficult to initally find what was happening. Things like: All started after a head job, the noise only occured under certain conditions (load/no load sort of thing), sounded like a lifter noise, no real evidence of the valves actually clippping the piston etc.

And I'm fairly sure we fixed it by fitting a shorter push rod to compensate for the head shave. And it was the front cyl on the left hand bank too. Is that No1??

I'm also sure that the different lenght push rods were avail from IH (at the time of course) along with a process of how to measure which one matched what head thickness.

Oldfulla

Did you mike the bores and the pistons?
Did it score a new piston or a used one?
Once pistons wear the skirt, they rock in the bore if the clearances are excessive.
New rings don't help if the slugs are rocking and I know it sounds really crook.