18.5 hp OHV Intek burning oil

[bob22cn]

Never use any added sealant when replacing head gaskets.

Thanks; I found this on Permatex site for this after I posted (duh):
"Not recommended for use on head gaskets or parts in contact with gasoline."
So much for a posting on another place.

 

[bertsmobile1]

Intek head gaskets are dirt cheap

I use the Stens ones where possible as they are a lot stronger than the OEM ones
After that I have some solid copper ones from Coppergasketsus because some heads just don't want to seal even after lapping.
I put that down to bad castings or bad post casting heat treatment it is possible to get aluminium to be harder on one side than the other,
BAck in the old days when you were doing a run the first 2 to 5 revolutions of the casting machine would all be considered as scrap because it takes that long for everything to get to full operating temperature ,

I assume I'll see oil squirting into the chamber on cranking?

No it will be sucking oilly crankcase vapour but you will see a gap hole or discolouration on one or both of the sealing faces.
Some of the tell tale signs of a blown head gasket are
1) White smoke coming out of the dip stick tube after the engine is turned off
2) knocking when the blades are turned on or drive engaged that smooths out
3) oil in the carburetter or air cleaner
4) oil dripping out the fuel pump brass vent
5) Plug oiling up / carbon fouling

 

[bob22cn]

Head is off:

and with gasket removed:

Arrows show where I think gasket failed. Agree?
Is this enough to cause my oil burning or do you think I need to go to the rings?

Thanks!

 

[Richard Milhous]

Ouch. Has that actually eaten into the block?

 

[bertsmobile1]

Yes that is the typical intek blown head gasket
I there is a deep groove it will need to be filled with your favourite liquid metal goop then the whole face smoothed & lapped.
I use a coarse stone followed by a sheet of wet & dry glued to a sheet of glass cut to the size of the wet & dry then flame smoothed on the edges .
The head needs the same treatment, but it is a lot easier to do.
B & S rough finish the heads & blocks deliberately so it grips the gasket like the teeth of a vice but some of them are just too rough and lead to a leak.
I have polished then dead smooth only to find the gasket blows out so I had to fit a solid copper head gasket.
OTOH this particular engine blew a head gasket every season or two so I had to do a couple of gasket replacements under warranty as a head gasket has a full 12 month warranty.
Coppergasketsus have intek head gaskets in a few thicknesses

 

[Richard Milhous]

Yes that is the typical intek blown head gasket
I there is a deep groove it will need to be filled with your favourite liquid metal goop then the whole face smoothed & lapped.
I use a coarse stone followed by a sheet of wet & dry glued to a sheet of glass cut to the size of the wet & dry then flame smoothed on the edges .
The head needs the same treatment, but it is a lot easier to do.
B & S rough finish the heads & blocks deliberately so it grips the gasket like the teeth of a vice but some of them are just too rough and lead to a leak.
I have polished then dead smooth only to find the gasket blows out so I had to fit a solid copper head gasket.
OTOH this particular engine blew a head gasket every season or two so I had to do a couple of gasket replacements under warranty as a head gasket has a full 12 month warranty.
Coppergasketsus have intek head gaskets in a few thicknesses

WHAT liquid metal goop? JB Weld will melt out. An old wrench once told me that lead wool (used for obsolete plumbing) would work. Never tried it.

 

[bertsmobile1]

I only use Devcon or POR 15
Both will make a suitable repair to heads
As for JB weld, 99% advertising hype 1% performance So I never use the stuff.
The trick is to buy from shops that engineers go to not the shops that DIY's go to .

 

[bob22cn]

Thankfully there is no groove or erosion of the head surface; that mark is just discoloration.

Is the recommendation to have the head and block surfaces smooth as possible or roughened similar to brake rotors are when new?

 

[bertsmobile1]

Just a light lap to flatten some of the high spots

 

[Richard Milhous]

I only use Devcon or POR 15
Both will make a suitable repair to heads
As for JB weld, 99% advertising hype 1% performance So I never use the stuff.
The trick is to buy from shops that engineers go to not the shops that DIY's go to .

JB Weld is awesome, in the right application. I have a power window switch still in service that I JB Welded 19 years ago, and some bicycle handles that get heavy, frequent use have served for 12 years now.

What's it's NOT is anything like a substitute for welding. It's nowhere near as strong as metal, can't stand any heat, and will only adhere to clean surfaces. It also takes at least a week to reach full strength, and will keep flowing for hours after mixing if you don't contain it. It's the advertising that's at fault, not the product. Which is just epoxy.