# Gasket Sealer



## twentysix by twentyfive (15 Dec 2019)

Hello knowledgeable folks. 

I think the gasket between the carburettor and the cylinder block on my two stroke engine may be leaking. That bit gets fairly hot. I don't think I can source a new gasket as the engine is no longer "supported". So does anyone have a recommended hot gasket sealer for this situation? 

TIA


----------



## Dirk (15 Dec 2019)

twentysix by twentyfive said:


> Hello knowledgeable folks.
> 
> I think the gasket between the carburettor and the cylinder block on my two stroke engine may be leaking. That bit gets fairly hot. I don't think I can source a new gasket as the engine is no longer "supported". So does anyone have a recommended hot gasket sealer for this situation?
> 
> TIA


What's the engine?


----------



## twentysix by twentyfive (15 Dec 2019)

Dirk said:


> What's the engine?


It's a chainsaw one. Jonsered CS2137 Not sure how I can extract engine details from that.

I've just been googling and gaskets are available for the CS2137 but before I spend even more dosh on this thing I'd like to do a cheap sealant type job first to see if that solves the problem.


----------



## midlife (15 Dec 2019)

Red coloured JTV rings a bell,?


----------



## Cycleops (15 Dec 2019)

I don't know if you can still get gasket paper but I imagine you can. Just a case of making a template on a piece of paper and transfering it to the gasket paper cutting it out with a steady hand and a sharp craft knife.


----------



## Stompier (15 Dec 2019)

Looking online, the OEM part looks like a composite gasket, so it's probably worth replacing it with a new one. The gasket shape looks quite complex to replace with a silicon sealant or jointing compound without making a mess.


----------



## Dirk (15 Dec 2019)

twentysix by twentyfive said:


> It's a chainsaw one. Jonsered CS2137 Not sure how I can extract engine details from that.
> 
> I've just been googling and gaskets are available for the CS2137 but before I spend even more dosh on this thing I'd like to do a cheap sealant type job first to see if that solves the problem.


Plain cardboard gasket smeared with grease would do the job.
Cut one out of a Cornflake packet.


----------



## screenman (15 Dec 2019)

Dirk said:


> Plain cardboard gasket smeared with grease would do the job.
> Cut one out of a Cornflake packet.



Do you think he could get away with a Rice Crispie packet gasket?


----------



## Dirk (15 Dec 2019)

screenman said:


> Do you think he could get away with a Rice Crispie packet gasket?


Even better. It will restore the snap, crackle and pop to his 2 stroke.


----------



## Moodyman (15 Dec 2019)

This should do it for a fiver from Euro Cat Parts:


----------



## sight-pin (15 Dec 2019)

We used to use Hylomar for gasket seal, and use a small ball peen hammer to cut most gaskets out.


----------



## keithmac (15 Dec 2019)

Used to be £45 a tube but down to £11 now. 

Best gasket sealant you can buy..


----------



## twentysix by twentyfive (15 Dec 2019)

Thanks all 



Dirk said:


> Plain cardboard gasket smeared with grease would do the job.
> Cut one out of a Cornflake packet.


Err - wouldn't the grease and cardboard carbonise and fail at engine temperatures?


----------



## keithmac (15 Dec 2019)

twentysix by twentyfive said:


> Thanks all
> 
> 
> Err - wouldn't the grease and cardboard carbonise and fail at engine temperatures?



The intake side of an engine is far cooler than the exhaust gas temperature.

If your cylinder inlet port gets to the combustion point of cardboard the piston would have seized in the barrel long ago..


----------



## Bazzer (15 Dec 2019)

Another recommendation for Hylomar or if you want metal to metal contact; Stag Wellseal. - But be warned, the latter should be considered as semi permanent.


----------



## twentysix by twentyfive (15 Dec 2019)

Bazzer said:


> Hylomar


Red or Blue?


----------



## biggs682 (15 Dec 2019)

Loctite do a vast range


----------



## twentysix by twentyfive (15 Dec 2019)

Stompier said:


> Looking online, the OEM part looks like a composite gasket, so it's probably worth replacing it with a new one. The gasket shape looks quite complex to replace with a silicon sealant or jointing compound without making a mess.


Ah I maybe have the wrong idea here. I sort of thought I'd add the sealer to the old gasket. The penny may be dropping it's either a new gasket or sealer not old gasket + sealer?


----------



## Dirk (15 Dec 2019)

twentysix by twentyfive said:


> Thanks all
> 
> 
> Err - wouldn't the grease and cardboard carbonise and fail at engine temperatures?


Carburettor/manifold interface doesn't get *that* hot. 
A greased paper gasket is good enough for the cylinder to crankcase joint on most bike engines and they don't have vapourised fuel cooling that joint.


----------



## twentysix by twentyfive (16 Dec 2019)

Dirk said:


> Carburettor/manifold interface doesn't get *that* hot.
> A greased paper gasket is good enough for the cylinder to crankcase joint on most bike engines and they don't have vapourised fuel cooling that joint.


Right. When I find some time I shall make up a cardboard and greased gasket and see how things go. I'll report back in due course (I hope). 

Thanks All


----------



## Bazzer (16 Dec 2019)

twentysix by twentyfive said:


> Red or Blue?


I have only ever used blue. Be warned to use gloves if you go down the Hylomar route. It can get messy.


----------



## keithmac (16 Dec 2019)

I'm not really a fan of Blue Hylomar but it would do the job.

Spent too long removing old Hylomar when rebuilding engines it seems. 

You just need a thin smear, people tend to slap it on thick from what I've experienced.

Wouldn't trust it on an engine build where a leak would mean a days labour or more to re-seal the cases.


----------



## Drago (29 Dec 2019)

Rolls Royce used to use hylomar blue at the factory.


----------



## Pale Rider (30 Dec 2019)

When I had my school holiday job at a local garage, the mechanics regarded gasket sealer as the preserve of the home bodger.

I suppose it has its place if specified by the manufacturer.

But as @keithmac says, it should always be used very sparingly.


----------



## keithmac (30 Dec 2019)

Pale Rider said:


> When I had my school holiday job at a local garage, the mechanics regarded gasket sealer as the preserve of the home bodger.
> 
> I suppose it has its place if specified by the manufacturer.
> 
> But as @keithmac says, it should always be used very sparingly.



All the Motorcycles I built have finely machined crankases matched in pairs, there is no gasket (due to tolerance issues with Main Bearing crank shells etc).

They have gasket sealant from the factory (the Three Bond Black is OEM Suzuki).

Majority of engine case covers are gasketless as well now, requiring a thin application of sealant.

I see it all the time where people have watched "Paint along with Nancy" then covered every single thing in a Blue mess.

As you say @Pale Rider there is a place for it but people tend to mad and paint it on everything.


----------



## Pale Rider (30 Dec 2019)

keithmac said:


> All the Motorcycles I built have finely machined crankases matched in pairs, there is no gasket (due to tolerance issues with Main Bearing crank shells etc).
> 
> They have gasket sealant from the factory (the Three Bond Black is OEM Suzuki).
> 
> ...



I don't think I would have prospered working on modern Japanese motorcycles because I lack the precision required.

Gasketless crankcases is an engineering world apart from the engine of a Ford Cortina.

Same as you, one of the reasons we took against gasket sealer was the number of times we had to clean up the mess a home mechanic had made while using it.

Threadlocker was another one.

We thought the correct fixing correctly tightened ought to be sufficient.

Things may have moved on in that respect because I gather some manufacturers recommend its use in some applications.


----------



## keithmac (30 Dec 2019)

I rebuilt an engine before Christmas (long story behind it but should have been a drop in replacement), took me nigh on an hour to remove the wrong and badly applied mess from the cases etc.

I did a Yamaha R1 as well, customer decided to take the cylinder head off and tip it upside down on garage floor to "have a look". 

All shims and shim buckets mixed up and covered in concrete dust, took and age to clean and then I had to start from scratch setting valve clearances, took hours of unnecessary work!.

Still, what can you do!.


----------



## Pale Rider (30 Dec 2019)

keithmac said:


> All shims and shim buckets mixed up



Similar upturned buckets and shims on the Jaguar straight six engines.

We had a tray box with different thickness shims in their own compartments.

I've seen the job done, but that is just the type of job that was beyond me.


----------



## keithmac (30 Dec 2019)

They use shim under bucket due to high rpm, I've seen FZR 250's that redline at 20,000 rpm!.

The R1 has a 20 valve head (most 4 cylinders are 16v). The valve clearance has to be set within 100's of a milimeter accuracy using various shims.

Shims and buckets are on bottom right of picture on clean paper.


----------



## Pale Rider (30 Dec 2019)

keithmac said:


> They use shim under bucket due to high rpm, I've seen FZR 250's that redline at 20,000 rpm!.
> 
> The R1 has a 20 valve head (most 4 cylinders are 16v). The valve clearance has to be set within 100's of a milimeter accuracy using various shims.
> 
> ...



You would certainly need to know what you are doing to do that job.

Looks like you use feeler gauges.

I suppose there's no other way of checking the gap.

I knacked one gauge by putting it under a rocker while the engine was ticking over.

Why I can't imagine, but the gauge was quickly hammered out of shape.

I believe proper metal workers reshape sheet by using a power tool called an English hammer which does a similar job - lots of quick, sharp, taps.


----------



## keithmac (30 Dec 2019)

Yeh it comes with experience same as everything really, I've rebuilt a fair few engines and bikes that have been stripped by others and boxed up..

Yes we still use feeler gauges, can't ever imagine they will be re-invented as long as shims are still about (koenigsegg are licensing camless heads for production cars but won't be mainstream for years).

Most cars are automatic hydraulic adjustment now, can't do that at high rpm though.

I've seen a few craftsmen use the English wheel to form curves our of flat steel and the English hammer as well, that will be a lost art soon unfortunately..


----------



## Pale Rider (30 Dec 2019)

keithmac said:


> Yeh it comes with experience same as everything really, I've rebuilt a fair few engines and bikes that have been stripped by others and boxed up..
> 
> Yes we still use feeler gauges, can't ever imagine they will be re-invented as long as shims are still about (koenigsegg are licensing camless heads for production cars but won't be mainstream for years).
> 
> ...



Ah, is there an English wheel as well?

Manual panel beating hammers and dollies is about as far as we ever got.

Even they were being used less as modern, thinner sheet steel was almost impossible to knock back into shape, meaning the repair was increasingly cut the panel off and fit a new one.


----------



## keithmac (30 Dec 2019)

If you're into Youtube there's some great videos, one below is an English Wheel in action.

I watch a chap called Abom79, he does some amazing work on the Lathes, not everyone's cup of tea though!.

Arthur Tussik is good to watch as well, nice to see true craftsmen at work.


View: https://youtu.be/W6GTMAMUee4


----------



## Ian H (30 Dec 2019)

In my day it Hermatite red, green, or gold.


----------

