6VE1 Isuzu Intake Gasket Failure



TEL: (03) 9372 3111, FAX: (03) 9372 3122

ACN: 006 798 492 ABN: 74 006 798 492




December 2011


This engine originally failed from the break-up of one of the catalytic convertors that fed abrasive material back into the engine via the EGR valve system. (Refer earlier newsletter)

Soon after a full recondition, excessive oil consumption was reported by the owner.


A look inside the throttle body clearly showed an engine in trouble with oily black residue everywhere.

When the engine was stripped down the engine was found to have been dusted. The inlet manifold gaskets were the source of the dust because they had both disintegrated and had been partly inhaled by the engine. All rings were worn out but no other damage had been done.

Whilst investigating this, contributions were sought from members of our group:

Echuca reported having had these gaskets fail once on them but they caught it early enough to just replace the non-genuine gaskets with genuine. It is worth noting that Echuca used a different brand after-market gasket than did North Melbourne. We need to consider that after-market gasket people are only packing materials from a variety of gasket manufacturers. It is most probable that two packaged brands use the same inlet gasket manufacturer.

Southern reported that they also had problems earlier when they first started working on the 6VE1. The same gaskets were crushing and breaking up.

The non-genuine gaskets are a three piece design with steel outer shims and the centre section made from a hard 4mm black plastic material. This material appears to be fragile and is disintegrating soon after assembly. It has to also be considered that over-tightening may be a contributing factor.


To eliminate this, Southern’s procedure has been to fit the inlet manifold for the mechanics and to use genuine gaskets and genuine inlet manifold bolt tension of 22 lbs/ft.

Their theory has been that mechanics are heavy-handed and were crushing and breaking the plastic material in the non-genuine gasket.

NOTE: The pricing for the genuine gaskets varies around the country:

As at December 2011:

Woolongong $88.00 per set

Melbourne $122.00 per set. (Capricorn)

The genuine gasket, GM-8972375380, is made as a four piece design using two outer steel shims and two inner composite material inner pieces. The assembly is flexible.

Our shop will not be using after-market inlet gaskets on this engine again and has the bolt tension specification documented for our assembly room. (We also only use a genuine rear main seal on this engine).

H James