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How to replace bottom end VN V6?

reddevil6

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Hey guys just got a VN V6 on gas. oh and its a VP motor. basicly it has a rely loud knock from the bottom end someone told me it was the harmonic balancer but someone i trust more said it was the bottom end baring. I will drive it for as long as i can, normally i would just put another motor in, but this one has good cams made to run on gas better so i would like to just replace the bottom end. but never done one before so not to sure how
 

DJ_Cosmic_Fire

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You will need to refer to your Gregory's Manual If attempting this yourself. Way too much detail to type out at this time for me, but basically you will be needing to pull the engine out of the bay for starters. Like you stated "just put another motor in" - so pull that motor then replace it with one with warranty of which you can get for 200 odd, but if you like the cam - then swap it when the motor is out..
 

Cheap6

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Determining if the balancer is broken or not should be easy with a visual inspection; if it's broken the rubber should be obviously torn away from the steel pulley. These engines are also known for cracking the flex plate, particularly if the beaming brace (bracket between the engine and trans.) has been bolted up incorrectly. You will be able to see that also, from underneath with the beaming brace removed.

If it is (a) worn main bearing and worn crank the cheapest way out will be the replacement used option ^. If they (it?) are not too bad you might get away with just dropping the sump and putting new bearing shells in without touching the crank. The crank doesn't have to be dropped to do that as you can rotate the upper shells in and out using a split pin in the oil holes in the crank and rotating the crank to slide the new shells in. You do need to support the engine in the engine bay and drop the K frame to access the sump.
 

Jxfwsf

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if it's something as serious as a bottom end bearing then driving for as long as you can would mean parking it right now and not even starting it..... problem with something majorly internal like this is there will be rogue bit of metal floating about doing serious damage....

It can block up the oil filter and thus the bypass valve will open up and the oil will no longer be filtered so every part of the engine will be damaged, including the "good" cam.
Oil is splashed around in the engine anyway and metal fragments will end up everywhere anyways.... ruining any serviceable parts, you'll have a worthless lump of scrap metal....

Easiest option is to just get another good engine, pull the cam out of the dying engine, pull the intake manifold and timing cover off the replacement engine, swap the bits over, replacing the intake manifold gaskets is generally a good idea on these engines as it's a common problem for them to deteriorate and leak, while you're at it put a new sump gasket on and you should have a good leak free second hand engine......

VN & VP engines are the same so it doesn't matter what it came out of (the only different one was the first of the VN's and it's basically the same anyways)
If looking to replace the engine I'd suggest finding a VR v6, they have a higher compression ratio than the earlier buick's that will suit lpg better.

The previous posts giving you advice are all good suggestions as well.
 
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