Why does my VLH die out?

[Peter Cooke]

Speaking of leaky manifolds has anyone had any experience with the PEEK intake manifold seals? Do they work that much better than brass ones, are they worth the money, etc,etc??

[T. Cotten]

Peter!

Yes, Yes,... and yes.

I pioneered the use of PEEK for this application a decade ago:
http://virtualindian.org/9techpeek.htm

Folks are cutting the material for themselves around the world, as often the manifold must be turned clean, and the seals custom-cut.

If you have an absolutely pristine manifold, you may be able to use mass-produced seals from http://www.enfieldracing.com/8.html

The material is expensive, but noble to the cause, and quite re-useable, as long as there were no blemishes upon the manifold to cause impressions.

Overheating a motor is much more expensive.

....Cotten

[Peter Cooke]

Thanks Cotten,
It seems to be a very worth while product and as you correctly say 'Overheating a motor is much more expensive'.
When I get back to Australia I'll check out the condition of my manifold and take it from there.
If I remember correctly it and the carb are both in very good condition, but I haven't seen them since Sep last year and my memory bank isn't getting any younger.....

[Rod K]

DSCF1677.jpgHi Peter...I can highly recommend Tom's manifold seals. I have them on three bikes. One way I've delt with the carb flange and spigot, if it's not too bad a shape, is to go to a glass shop and get a square of quarter inch plate glass. Have them drill a
1 5/8 or 1 3/4 hole in the middle. Tape a piece of emery paper to the glass and cut the hole open with an exacto knife. then you can work the flange face on the emery paper.

Of course if the flange is too bad then you have to trim the spigot off...I have not had to dothat yet...Rod

[T. Cotten]

Rod!

If they have a spigot, I suggest a simple lathe cut.

....Cotten

[Peter Cooke]

Thanks for the recommendation Rod and the glass idea. I am a machinist by trade so have no issue using a lathe if required but hopefully I won't need to.

[sirhrmechanic]

Had not had time to jump in on this... but a couple of thoughts...

The Intake Leak issue was very much the first thing that jumped to mind.

That said, someone above mentioned condensers. Nowadays on cars, it's the first thing we replace when we have running issues. They are cheap, but a &%^$# to diagnose. And a bad one can allow a car to idle, but die out and go flat under power. I used to think that a condenser either worked or not. No in-between. But this is not true. An engine can run with problematic condenser and exhibit the symptoms you describe.

We have an old saying in vintage cars "99 percent of fuel problems are the ignition." Most people go right to the carbs because they have knobs. And as men, we twiddle knobs knowingly while nodding to ourselves that "oh yes, that sounds better." The reality is that once a carb is set... short of dirt or restriction or 10K feet of altitude change... it's set forever. Adjust it right. Adjust it once. And leave it the heck alone! It does not just 'happen' to get out of adjustment. The ignition system, on the other hand, has to be kept clean, in time, gapped, etc. etc. etc. Before anyone twiddles carb knobs... check your spark from plug gaps to plug wires; from timers to condensers. More often than not, therein lies your problem.

That said... manifold leaks, etc. are also common on twins. And on car engines. And can be fairly easily diagnosed. But hopefully this will give everyone a bit of 'food for thought' next time they have a bad runner.

Cheers,

Sirhr

[c.o.]

That's very sound advice Sirhr. I'll be the first to admit that I've reached down and "twiddled" with the carb when I really had an ignition issue. Fuel or spark??? Usually spark if the carb was initially functioning properly... I absolutely agree!!!

Oh yeah, PEEK is good stuff!!!

[Peter Cooke]

Jim,
What's the latest? Did the new gasket help or is there more to the problem?

[Jim]

Jim,
What's the latest? Did the new gasket help or is there more to the problem?

Hi Pete, thanks for the UPDATE reminder. YES, my problems were with the gasket. I put the new one on and have ridden about 10-15 miles and it ran pretty good too; before it ran out of gas. HAHA! Seriously... I rode home, but the very next time I started it up, it ran for about 30 seconds and then quit. Naturally, I figured something was really bad again. I kicked again, and it sputtered and then I pulled the choke up and it smoothed out for a few seconds... and then quit again. My mind said to me... check the gas tank... yep... empty. Well, at least that fix is easy! I still need to maybe "tweak" the carb adjustments yet, as it seems to "lug" at low speeds at say... 20-30 mph, but it is so close that I am just saying that it works! I remember the '36 doing that way back when before I ever had any issues with the manifold gasket. I am wondering if it isn't because it is a M344 carb for an Indian and not the M41L carb it is supposed to have. Either way, I am 95% satisfied with the way it runs now.

Thanks for asking and reminding me to POST my results... sorry for the absence.

[Steve Slocombe]

Whoa Jim! Now you tell us it has an incorrect carburettor? The mighty 80 cubic inch motor needs the 1 1/8" venturi, not the 1 1/16" one, and there is some evidence Harley polished the intake manifold and used a 9/64" fuel inlet instead of 1/8" on the 1935/6 eighties. And does the Indian carb have a slotted venturi while the Harley one uses a vented body? There is plenty of room for mix and match difficulties here.

[Jim]

Whoa Jim! Now you tell us it has an incorrect carburettor? The mighty 80 cubic inch motor needs the 1 1/8" venturi, not the 1 1/16" one, and there is some evidence Harley polished the intake manifold and used a 9/64" fuel inlet instead of 1/8" on the 1935/6 eighties. And does the Indian carb have a slotted venturi while the Harley one uses a vented body? There is plenty of room for mix and match difficulties here.

HAHA!!!... :^) Hi Steve, actually I mentioned that it had an Indian M344 in the very first post. ;^) Sorry, I never looked at the M344 that close to see if it has a slotted venturi or not and to tell the truth, I wouldn't have known any different to what my VLH was supposed to have anyway. I also never knew that the VLH 80s had a 9/64ths fuel line either.... maybe time for some VLH updates on my bike. 8^)

Yes, I have your VL Restoration book too, but not the newest version. Great stuff in it.

Isn't this fun?

[T. Cotten]

Steve!

A long time ago, I overbored a UL to 80" that had absolutely no problem with a 1 1/16" venturi. It pulled like a tractor as fast as anyone should want to go.
Was I just lucky?

Can you suggest how the throat-venting of the nozzle could be a problem for the Harley?
There's got to be a reason for Indian's unusual nozzles.

Thanks in advance,

....Cotten

[Steve Slocombe]

Dear Cotten, I'm thinking mixing the vented Indian venturis with the Harley vented carburettor bodies, and of course putting the unvented Linkert venturis in the mostly unvented Indian carb bodies, would not help riders to get smooth running. We find the same problem with people using the good old M88 Linkert carb on the flathead Big Twins. The 15/16" slotted venturi and fixed jet for the 45 small twins will run on the larger capacity bikes, but switching to a larger unvented venturi and an adjustable main needle does not always work out better. I'm sure your 80 ran fine with a 1 1/16" venturi, with the 1 1/8" more for top speed and bragging. Harley advertised the 1936 VLH at 38 bhp, which is going some on a 5.8 to 1 compression flathead with stock cams. And Jim, yes this is fun, I'm breaking in a 1933 VLE and a 1936 VLH at the moment and having a blast.