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Author Topic: heads off the 6/1, should do gaskets, right?  (Read 1412 times)

glort

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Re: heads off the 6/1, should do gaskets, right?
« Reply #30 on: June 01, 2019, 04:52:56 AM »
I modified to run as a pseudo diesel on methanol using Mark Cherry's Smartplug invention.
 

Did they work Bruce?

I looked up the website but it's more non functioning than working.
Can't find any new info on the things in the last year so I guess they are Kaput now.

I always did want to be able to reliably run a petrol engine, mainly a 2 stroke on Diesel or Veg.

BruceM

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Re: heads off the 6/1, should do gaskets, right?
« Reply #31 on: June 01, 2019, 05:51:26 AM »
Yes, Mark Cherry was legit, he just couldn't sell his idea to the automotive industry. He had a contract with Darpa as part of the "one fuel forward" research program.  My version of his original patent worked fine in my Honda 4cy outboard running methanol. I only had to apply current for starting. Increasing compression and getting enough fuel flow (double the normal gasoline flow rate) from the carb were challenging, but it did work quite well.

In his later versions Mark Cherry was varying the current to the platinum element to adjust ignition timing. 

I don't know if it's possible to run a gas engine on oil using his method.  I know he had success with aqueous fuels (less refined alcohol), with the benefit for very low NOX due to all the water and the lower combustion temps.  Again, no interest from industry.


veggie

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Re: heads off the 6/1, should do gaskets, right?
« Reply #32 on: June 20, 2019, 05:40:17 PM »
tyssniffen,

When you re-assemble the head, consider spraying the head gasket on both sides with Permatex Copper Gasket coating.
Its adds additional sealing for the water passage ports.
Here's how I did mine ...
- 6/1 GM90 Listeroid - Delco 33si Alternator
- Changfa R175 - Lease/Neville Alternator
- Kubota Z482 - 4kw
- JiangDong R165 Air cooled - 2 kw

BruceM

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Re: heads off the 6/1, should do gaskets, right?
« Reply #33 on: June 20, 2019, 06:09:30 PM »
+1 I've used the same copper spray when reusing head gaskets.  It does work.

Water passage sealing is a big problem for Listeroids with liners, with a protruding lip. Best to address head and cylinder top flatness, and lip protrusion if you're having problems with leaks. The protrusion of the liner causes concave warping of the head, which causes insufficient pressure at coolant passages.

The stock Rajkot copper/asbestos gaskets with asbestos soaked with Permatex aviation gasket sealer is the best for the bad head/liner protrusion situation; I tried everything before finally fixing the problem. Copper spray does also help seal the water passages. Combined it was still only a 400 hour solution before leaks.

The best fix is to reduce the protrusion to under 0.005 inches (5 mils) and flatten the head and cylinder top.  I used the classic farmer fix- sandpaper with spray contact cement on plate glass on non-slip foam shelf liner on cast iron saw top. 

Lots of elbow grease to flatten the concave head but it's doable.  A file and careful work for the liner protrusion prevents another concavity.




mikenash

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Re: heads off the 6/1, should do gaskets, right?
« Reply #34 on: June 20, 2019, 07:35:31 PM »
+1 I've used the same copper spray when reusing head gaskets.  It does work.

Water passage sealing is a big problem for Listeroids with liners, with a protruding lip. Best to address head and cylinder top flatness, and lip protrusion if you're having problems with leaks. The protrusion of the liner causes concave warping of the head, which causes insufficient pressure at coolant passages.

The stock Rajkot copper/asbestos gaskets with asbestos soaked with Permatex aviation gasket sealer is the best for the bad head/liner protrusion situation; I tried everything before finally fixing the problem. Copper spray does also help seal the water passages. Combined it was still only a 400 hour solution before leaks.

The best fix is to reduce the protrusion to under 0.005 inches (5 mils) and flatten the head and cylinder top.  I used the classic farmer fix- sandpaper with spray contact cement on plate glass on non-slip foam shelf liner on cast iron saw top. 

Lots of elbow grease to flatten the concave head but it's doable.  A file and careful work for the liner protrusion prevents another concavity.

Hi Bruce and others

I have just been reading up on this as I'm interested in head and base gasket sealing at the moment

I would guess in a metric environment that liner protrusion is more like a tenth of a millimetre?  If it's five thou?

Cheers


BruceM

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Re: heads off the 6/1, should do gaskets, right?
« Reply #35 on: June 21, 2019, 01:18:46 AM »
6 mils or 0.006 inches is the thickness of a standard sheet of copy paper. 
I'd shoot for 0.1 millimeter = 4 mils or a shade under.  More protrusion just means more leaks at 200 hrs+.

What I used was a feeler gauge next to the lip, and then ran my fingernail back and forth to determine if I was down to the feeler height yet. 

One thing to check carefully is that the cylinder liner isn't being held up by some sloppy machining of the liner or cylinder.  You may be able to rectify that with some careful dremel work. If you are having the machine shop do it properly, and the cylinder looks good, then they will cut the shoulder of the liner.  I used a file to take down the protrusion, with a feeler gauge to test regularly all around and a lot of patience. I smoothed it with a disc sander.

No worries at all for the Lister clones or originals- they have no liner thus no protrusion.

tyssniffen

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Re: heads off the 6/1, should do gaskets, right?
« Reply #36 on: September 25, 2019, 06:51:17 PM »
 So, update on all this:

I finally got the proper copper sheet gaskets, and laptop the valves, and talked it all down and it is starting up no problem.   I finally got the proper copper sheet gaskets, and laptop the valves, and torqued it all down and it is starting up no problem.

 However, I did not do any spray, cause I didnít see this post until now. And, sure enough, I have what looks like water leaking out at the bolts on top.    At really zero run hours.

 So, do I take it all down again and spread and put it back together?

( quite honestly, I really donít understand this whole protrusion discussion. The liner of the cylinder protrudes above the plane of the head? Mine does not protrude. What protrusion are you talking about? )

veggie

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Re: heads off the 6/1, should do gaskets, right?
« Reply #37 on: September 26, 2019, 01:00:05 AM »
That's what happened to mine right from the factory. And that's why there is a picture above of my engine with the head off.
It's a pain in the butt.
The steel cylinder liner which is pressed into the cast iron cylinder/water jacket is sitting too high above the surface of the cast iron deck.
When the head is installed the protruding cylinder prevents the water jacket portion of the gasket from being adequately crushed.
Mine was protruding about .050" above the deck, and it should only protrude 0.003" to 0.005"
There are various ways to correct this. In my case I had to get a machinist friend to press out the liner, machine some material off it, and press it back into the block.
Others may have an easier fix.
Welcome to the world of Rajkot  >:(

- 6/1 GM90 Listeroid - Delco 33si Alternator
- Changfa R175 - Lease/Neville Alternator
- Kubota Z482 - 4kw
- JiangDong R165 Air cooled - 2 kw

BruceM

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Re: heads off the 6/1, should do gaskets, right?
« Reply #38 on: September 26, 2019, 02:17:12 AM »
Yes, the liner lip will be above the top of the cylinder.  That's the protrusion we're talking about.  It's highly unlikely that your liner does not protrude, unless you have a clone which has no liner.  If there is no liner, it will not be sticking out below the bottom of the cylinder and there will be no seam about 1/2 inch around the cylinder bore on the head. Rajkot does make cylinders with no liner. If you got one, then your head or cylinder top is not flat, and must be made so per steps 2 and 3 below.

After the head has been torqued down on the protruding liner, it will become concave.  Then even if you fix the protrusion, it will leak at the water passages.  So three things must be done if you want to permanently fix the water leak issue:
1. Get the liner protrusion fixed by a machine shop unless you are very handy, careful and good with precision work and can do it yourself. Ask for 0.003" +- 0.002 protrusion.
2. Get the head mating surface flattened by a machine shop, unless you are very handy, careful and good with precision work and can do it yourself.
3.It's best to have the top of the cylinder flattened by the machine shop also.

With these done, any head gasket that fits will work and you won't have leaks.

I hope this is clear.