SCARY start-up rod/valve knock/clatter!

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Feb 16, 2012 | 07:06 AM

#21

LOCOMOengineer

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From: Mt. Vernon IL

SOUNDS LIKE SOUND ADVISE WITH RESPECT TO THE SOUNDS! *chuckles* thanks! I am really impressed with the insight and knowledge base that is making quite the showing about my lil green wagon s=0)

Feb 17, 2012 | 05:15 AM

#22

sixstringslut

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From: NW OH

I would just baby it until the weather warms up, meanwhile, save your money for a reman long-block as a worst case scenario. That way you will only have to cycle for a few days other than weeks of machining and ordering parts. LOL

Do the little things that were mentioned before but when it comes to bearings, that's a new ball-game. You don't want to be rushed through anything like that.

Feb 18, 2012 | 02:15 PM

#23

abecedarian

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From: Temecula Valley, CA

Quote:

Originally Posted by LOCOMOengineer

so ESSENTIALLY... under a worn journal condition its likely sounds reasonable to assume and commit on the onset to doing the crank & cam bearings, shim the buckets and maybe just maybe ill end up turning the crank & or cam. - and turning ( I realize) means oversize bearings

:wabbit2:

i should plan this whole thing better. perhaps even PURCHASE an entire rebuild kit... and just get jiggy with the thing.

Ive got access to a cherry-picker & engine rack. I MIGHT just be better off investing a deeper commitment... lil more money and do the damned thing the way a real pro would do it, long block mounted nice and accessible, flippable on a rack and just PLAN to ride my bike to work and tell the landlord what im planning because this thing aint likely to happen in a few hours LOL.

If oil is leaking around the big end, it's possible there's not enough getting up to the small end, I wouldn't necessarily expect that the little end of the rods are worn, but I would expect the need to check them: if you've got the rods out, why wouldn't you check them? The bushings there need checked.

I'm not sure I'd purchase a full kit without knowing I need all the parts; get what I mean? On the other hand, a full rebuild won't necessarily hurt anything- it's just like shooting with a scatter gun to make sure you kill the vermin regardless of 100 or 1 vermin.

The cam... you'd have to mic the journals to know. But it is the 3V, so the rear cylinders' valves need special attention too.

Feb 18, 2012 | 05:19 PM

#24

Jomoka

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From: St. Louis MO

Actual loose rod bearings aren't really quieted down that much by oil pressure, they'll knock in certain conditions regardless. I'd tend toward deflated lifters or plain old piston slap. When pistons are cold, they shrink, on a somewhat worn motor they can have enough clearance to rattle some as they hit TDC and do an abrupt 180. When they warm up a little, they get quiet again.

Feb 20, 2012 | 01:31 PM

#25

abecedarian

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From: Temecula Valley, CA

Quote:

Originally Posted by Jomoka

Actual loose rod bearings aren't really quieted down that much by oil pressure, they'll knock in certain conditions regardless.
...

Yes, rods will knock in certain conditions, as in there's not enough oil retained within the bearing surfaces to prevent metal-to-metal contact... but either increased oil flow or oil viscosity to an extent can prevent that.

Quote:

I'd tend toward deflated lifters or plain old piston slap.
When pistons are cold, they shrink, on a somewhat worn motor they can have enough clearance to rattle some as they hit TDC and do an abrupt 180. When they warm up a little, they get quiet again.

You mean like most Diesel engines do?

Anyhow.

I would normally agree that "deflated lifters" (I call them collapsed followers) would cause noise, at a rate 1/2 the engine RPM. But that's only relevant to hydraulic lifters (followers) which the 3VZE has not: they are solid and require "shims" to take up follower clearances.

???