Thwaites Dumper help needed ID Engine

[Robt]

Hello everyone.. After a bit of advice, my little

old Thwaites 4x4 Dumper needs a engine rebuild to the top end.
The bore looks very good and ring's OK, but it was blowing a bit from the cylinder head. There was no gasket at all, I had it in my mind there should possibly be a copper ring?
We think it is a Petter of some description?
If anyone can help with the model type of the engine be a great help.
As would if anyone knows of anyone who supplies the spares still.
Cheers

 

[JD450A]

Petter PAZ1, I reckon https://www.stationaryengineparts.com/Petter-PAZ1-Engine-Spares/

 

[Robt]

Thanks I will have a look at the link.. I was fairly sure it was a Petter but just which one wuz the issue

 

[Robt]

Do you know if they have a copper ring as a head gasket, or is it a metal to metal fit between the barrel and head face? My mate has a feeling its going to be a case of getting the head machined up to get a seal..

 

[GazCro]

Not 100% sure but i think there should be a copper gasket or shim. If so shims vary in thickness to adjust compression.

 

[JD450A]

Copper Gasket.

 

[GazCro]

Copper Gasket.

Sure there are shims as well though aren't there. Possibly removed to up compression for starting to get round worn rings and barrel?

 

[JD450A]

Sure there are shims as well though aren't there. Possibly removed to up compression for starting to get round worn rings and barrel?

From memory the shims are to alter the clyndr height to allow more fuel to be injected and thus more power.

 

[Robt]

Sorry for the late reply.. Yes there are shims on the base of the cylinder barrel..
The compression leakage is between the barrel and the head seal.
Usually there is a head gasket of some sort, hence me thinking should it have a copper ring as a head gasket.
The bloke helping me out has wondered if it is just a face to face fit and it may want resurfacing on a milling machine?

 

[GazCro]

Sorry for the late reply.. Yes there are shims on the base of the cylinder barrel..
The compression leakage is between the barrel and the head seal.
Usually there is a head gasket of some sort, hence me thinking should it have a copper ring as a head gasket.
The bloke helping me out has wondered if it is just a face to face fit and it may want resurfacing on a milling machine?

Don't think so should be a copper gasket. Have you checked the link rory sent looks like theres a copper gasket in the top set kit.

 

[GazCro]

Sorry for the late reply.. Yes there are shims on the base of the cylinder barrel..
The compression leakage is between the barrel and the head seal.
Usually there is a head gasket of some sort, hence me thinking should it have a copper ring as a head gasket.
The bloke helping me out has wondered if it is just a face to face fit and it may want resurfacing on a milling machine?

Don't think so should be a copper gasket. Have you checked the link rory sent looks like theres a copper gasket in the top set kit.

 

[Robt]

Don't think so should be a copper gasket. Have you checked the link rory sent looks like theres a copper gasket in the top set kit.

Thanks for that, I keep chasing so many things at the moment can't get to check it out I will try calling the spares place tomorrow as really need to get the dumper done