Robin Subaru Engine ID

[Frank Sorbello]

I need to order rocker cover gaskets for my 1999 pt 422. On Robin's website there is an old type and a new type 22hp engine. How do you determine which engine type you have through the serial number?

My serial number is 4531 1003376.

Thanks

Frank

 

[MossRoad]

You could try calling Jack's small engine. They might be able to help.

Lawn Mower Parts

 

[Clumber]

I need to order rocker cover gaskets for my 1999 pt 422. On Robin's website there is an old type and a new type 22hp engine. How do you determine which engine type you have through the serial number?

My serial number is 4531 1003376.

Thanks

Frank

You need the Production number for you engine, located just above the serial number. For example for my PT-425 it is EH720DS00117112.


Then go to the Robin Parts Catalog (ordered by Specification, that is, the Production number):
https://euc.robin-fhi.co.jp/parts_catalog/model.aspx?lang=e
Look up the 1st 5 digits of your PN to get a list of productions for your engine.

You can also Google the PN leaving out the last 4 digits. I found a site that has better prices than Jack's on several parts:
Subaru / Robin EH720DS0011 Parts List and Diagram : eReplacementParts.com

 

[Frank Sorbello]

Hi, I bought new valve cover gaskets from Jacks Small Engines. Cleaned the old surfaces and replaced. I still have one side that is dripping oil after running for several minutes. So after running the tractor for a while there is quite a bit of oil in the tub. Would it hurt to double up the gasket?

 

[ponytug]

Dear Frank,

It isn't generally recommended to double gaskets, as you are introducing a third potential leak area, and an area that may be more prone to leakage than the existing areas. You also are changing the load on the screws holding the cover on, etc.

Is there some reason to think that the gasket wouldn't have seated correctly? e.g. a dented cover? If there is some reason, you may be better off making a gasket with gasket compound and letting it set.

Are you sure that the leak is coming from the valve cover seal, and not somewhere else? e.g. a cracked cover or a pin hole leak in the cover, or somewhere else entirely?

All the best,

Peter

 

[Frank Sorbello]

I doubled up the gasket on the side that is leaking. It is still leaking. I am afraid if I tighten too much I might crack something.

I also noticed when driving today it didn't have much power. I pulled the left plug while running and it shut right down. Started back up and this time pulled the right plug wire and it kept running. I guess I have a problem with the one cylinder.

 

[ponytug]

Dear Frank,

Sorry to hear about the problem, but the good news is that you are narrowing it down. Have you replaced the spark plug on that side yet? It is an inexpensive thing to try. Otherwise, I am afraid you are looking at something a little more major, like a cross threaded spark plug seat, or a loose, or cracked head.

Please keep us posted.

All the best,

Peter

I doubled up the gasket on the side that is leaking. It is still leaking. I am afraid if I tighten too much I might crack something.

I also noticed when driving today it didn't have much power. I pulled the left plug while running and it shut right down. Started back up and this time pulled the right plug wire and it kept running. I guess I have a problem with the one cylinder.