jjwalker
12-01-04, 04:10 PM
::::Common problems with the 60v6 and how to deal with them::::
The point of this article is to explain the most common problems associate with the 60v6. This is in no way trying to discourage modification, but to inform 60v6 owners of some of the shortfalls of the stock 60v6 motor. All of these problems can be avoided with the exception of one, so dont be afraid!
Intake manifold gaskets:
This is the one you just have to live with, and cannot really be completely avoided.
The intake manifold on the 60v6 is very unique. It makes up 25% of the head. The reason this design is so failure prone is because you have 2 gasketing surfaces at different angles contacting each other. If you take a look ( no pics sorry) you will see that the valve cover goes partially over a peice of the intake. For and example of these 2 mating surfaces trake a look at the illistration below.
Valve cover
______________
............\'''''''''''''''
..Head.....\'''''''''''''Intake
...............\''''''''''''
.................\''''''''''''''
The real problems lies in the materials the 3 objetcs are made from, so this mainly applies to cast iron heads, but the problems still slightly remaisn in the aluminum head motors. Your head is cast iron, and the intake manifold is aluminum. These are 2 completely different metals that shrink and expand at very different rates, which puts extreme stress on the valve cover, and intake to head gaskets at this point. So you will have 3 different possibilites of gasket failure. The valve cover can leak here, the intake gasket can leak coolant into a cylinder, or both. Usually the valve cover gasket will seep very lightly here, and is very common. Now the intake leaking coolant is a nightmare. If you notice ANY slight signs of coolant leaking into the cylinder ( oil that is milky, excesive water and or coolant smell in exhaust) Then 9 times out of 10 your problems is here!
Pistons:
The factory pistons on the 60v6 arent made for abuse. The rods can take up to 7000 rpm, and the factory crank is forged, but the pistons cannot take 7000 rpm. DO NOT rev your 60v6 engine over 5000 rpm UNLESS you have strengthened reciprocating parts, mainly the pistons. They have a tendency to crack at the wrist pin. A good set of forged pistons should allow you to be harder on it, but not always. I have a cracked piston as we speak and it is forged, but then again at the time I was driving it like I hated it.
Modified small journal 350 piston rods can be used if you need that extra sense of security, or you can order custom ones. There are also many manufacturers of custom pistons for the 60v6.
Rear main seal:
The rear main on the 60v6 has a bad tendency to leak and usually gets quiet bad on high mileage motors. The stock seal is a 2 peice but there is a replacement 1 peice rear seal that will solve this problem.
Old style blocks (85 & older)
The original gen 1 60v6 blocks had .65 main bearings that had a tendency to fail. If you plan on replacing your motor get an 87 or older engine block ( 86 motors could have either .65 or .67 mains). The .67 mains are much stronger.
The point of this article is to explain the most common problems associate with the 60v6. This is in no way trying to discourage modification, but to inform 60v6 owners of some of the shortfalls of the stock 60v6 motor. All of these problems can be avoided with the exception of one, so dont be afraid!
Intake manifold gaskets:
This is the one you just have to live with, and cannot really be completely avoided.
The intake manifold on the 60v6 is very unique. It makes up 25% of the head. The reason this design is so failure prone is because you have 2 gasketing surfaces at different angles contacting each other. If you take a look ( no pics sorry) you will see that the valve cover goes partially over a peice of the intake. For and example of these 2 mating surfaces trake a look at the illistration below.
Valve cover
______________
............\'''''''''''''''
..Head.....\'''''''''''''Intake
...............\''''''''''''
.................\''''''''''''''
The real problems lies in the materials the 3 objetcs are made from, so this mainly applies to cast iron heads, but the problems still slightly remaisn in the aluminum head motors. Your head is cast iron, and the intake manifold is aluminum. These are 2 completely different metals that shrink and expand at very different rates, which puts extreme stress on the valve cover, and intake to head gaskets at this point. So you will have 3 different possibilites of gasket failure. The valve cover can leak here, the intake gasket can leak coolant into a cylinder, or both. Usually the valve cover gasket will seep very lightly here, and is very common. Now the intake leaking coolant is a nightmare. If you notice ANY slight signs of coolant leaking into the cylinder ( oil that is milky, excesive water and or coolant smell in exhaust) Then 9 times out of 10 your problems is here!
Pistons:
The factory pistons on the 60v6 arent made for abuse. The rods can take up to 7000 rpm, and the factory crank is forged, but the pistons cannot take 7000 rpm. DO NOT rev your 60v6 engine over 5000 rpm UNLESS you have strengthened reciprocating parts, mainly the pistons. They have a tendency to crack at the wrist pin. A good set of forged pistons should allow you to be harder on it, but not always. I have a cracked piston as we speak and it is forged, but then again at the time I was driving it like I hated it.
Modified small journal 350 piston rods can be used if you need that extra sense of security, or you can order custom ones. There are also many manufacturers of custom pistons for the 60v6.
Rear main seal:
The rear main on the 60v6 has a bad tendency to leak and usually gets quiet bad on high mileage motors. The stock seal is a 2 peice but there is a replacement 1 peice rear seal that will solve this problem.
Old style blocks (85 & older)
The original gen 1 60v6 blocks had .65 main bearings that had a tendency to fail. If you plan on replacing your motor get an 87 or older engine block ( 86 motors could have either .65 or .67 mains). The .67 mains are much stronger.