Eagler's Nest

Engines => 2 Cylinder => 1/2 vw => Topic started by: Bird Dog on April 04, 2021, 11:12:56 AM

Title: !/2 VW timing issues
Post by: Bird Dog on April 04, 2021, 11:12:56 AM

HI All, I'm new to the forum. I recently bought an LE that was mostly built by an experienced builder, but sat in the hangar for years unfinished. He said he built the motor and test ran it for aprox. 5 hrs. Since sitting so long I decided to remove the heads, cyls., to check out the engine. everything looked new as he said with a little carbon indicating it had run. the exterior of the engine was looking pretty rugged after years of sitting so I decided to remove and clean up and paint the motor. I looks great now. but when putting things back together I lost my timing mark. Now I cant seem to figure out how to time the motor without #1 cyl. being there. can some one please tell me how to time this thing?

Title: Re: !/2 VW timing issues
Post by: Kamcoman77 on April 04, 2021, 02:56:56 PM

Put whichever cylinder you want to be #1 at top dead center (TDC) on the compression stroke. Mark your prop hub in line with the split in the case as TDC (0°). Install your distributor or magneto so it fires at the degrees you want.

Title: Re: !/2 VW timing issues
Post by: Bird Dog on April 04, 2021, 04:53:06 PM

Thanks for the reply. It is a distributor. So essentially the trick would be to ignore mark on the prop hub indicating TDC of #1 cyl. Turn the prop to TDC of #4 on compression stroke.make a mark for TDC #4 and time it to that mark. Thanks ill give that a try.

Title: Re: !/2 VW timing issues
Post by: Kamcoman77 on April 04, 2021, 05:06:17 PM

Sounds like you got it. The engine does not care what cylinder you use for #1 as long as timing is based on the TDC of the cylinder you choose.

Title: Re: !/2 VW timing issues
Post by: Bird Dog on April 24, 2021, 09:22:49 PM

Well I set the timing up as it should be. I installed a new pertronics distributor. Have great spark. Engine has good compression. But I still can't get it to start. It has fuel as well. It just doesn't seem to want to run. It pops but just won't keep going. I'm at a loss as to what I should do next. Any suggestions would be much appreciated.

Title: Re: !/2 VW timing issues
Post by: Kamcoman77 on April 25, 2021, 06:17:25 AM

Awfully hard to say without being there, but as a general rule.... if it pops but won't run there is not enough fuel getting to the cylinders. To check this, you could remove the spark plugs, put a few drops (not a squirt) of gas in each plug hole. Reinstall plugs and try to fire right away. If it tries to run a little better than before, you have your answer. Good luck! If it backfires out one of the carbs, it is probably 180° out on the timing, Like Dan says.

Title: Re: !/2 VW timing issues
Post by: Bird Dog on April 25, 2021, 07:16:56 AM

Thanks Komcoman77 for your replies. I'll try that.

Title: Re: !/2 VW timing issues
Post by: Dan_ on April 25, 2021, 08:26:57 AM

Could it 180 degrees out of time..?  Make sure the plug that is going to fire is matched to the cylinder that is coming up on compression.

Title: Re: !/2 VW timing issues
Post by: Bird Dog on April 25, 2021, 04:51:41 PM

I've checked that then some. I ordered a new fuel pump not that the I really think the old one is bad just eliminating possibilities. It was only 25 bucks anyway. I'm wondering if the carburetors are plugged up.
The old guy I bought it from said he ran it 5 hrs. If he used ethanol gas it could be they're gummed up. I may go through the carbs.
 Thanks for your help.

Title: Re: !/2 VW timing issues
Post by: Kamcoman77 on April 25, 2021, 05:34:47 PM

It certainly wouldn't hurt to remove the float bowls and check the needles & seats. If you find any white gummy junk or white powder in the bowls, better take all the jets out and blow them clean with compressed air or spray can carb cleaner. Here is a short YouTube video showing some bad stuff: https://www.youtube.com/watch?v=0H9OssJRSEs

Title: Re: !/2 VW timing issues
Post by: Bird Dog on April 26, 2021, 07:45:22 AM

Thanks again ill do that