TheSamba.com :: View topic - I think I done broke it...Help for a noob?

Sun May 06, 2012 7:24 pm

I am restoring an old dune buggy that my dad built 35 years ago. It sat for about 15 years without being run. I stripped it all down, broke down the engine and cleaned everything up. After I put it all together, I turned the key and it started right up! I drove it around my house, and it seemed to be running just fine. The brakes needed work, so I spent the last week redoing the brakes, and when I got it all put back together and turned the key, something horrible happened. There was a whining sound (starter) but the engine was not firing. The pulleys in the rear were rotating with the starter, but it sounded like there was no compression from the engine. Does this sound at all familiar? I don't even know where to start with this.

Thanks for any help.

Here is a video of the sound.

http://www.youtube.com/watch?v=1Hfg2DjutUg

Sun May 06, 2012 10:09 pm

when you broke the engine down, did you use the same pistons and cylinders? if so, did you hone them before reinstalling? you really need to check compression next. you are getting a little compression and it did run before so also check for spark. it might have ran with the limited compression before.

what kind of starter do you have. a high torque or even a autostick starter will spin a engine that fast which led me to the no spark or timing off issue if you have one.

long shot. do you have the valves too tight. too tight would cause the valves to stay open and the cylinders would never build up pressure.

good luck.

welcome to the forum.

Sun May 06, 2012 10:25 pm

I used all the same cylinders and pistons. Despite their age, there were very few miles on them and everything still looked good (to me anyway).

I am going to go through tomorrow and check all of the ignition stuff again to verify that I am getting spark all around.

This noise has happened with 2 starters now. This morning, I had the original starter on there. Thinking that it was the cause of the problem, I replaced it with (essentially) the same thing. Same sound emerged, so I feel like I can safely rule out the starter.

The valves seem to be moving just fine. I pulled of the covers, and hand cranked the engine and all 8 valves moved beautifully.

Another friend suggested flywheel damage, which is a possibility. I guess the only way to find out for sure is to pull the motor :(

Thank you for the suggestions. I will be busy tomorrow.

Sun May 06, 2012 11:01 pm

Ok, if the pulleys were spinning then so was the flywheel. So rule that out. Before you rip the motor back out, check for 1) spark, 2)static timing, 3)fuel dilevery, 4) compression test. The first three should take all of 15 minutes.

Sun May 06, 2012 11:18 pm

johnnyfresno wrote: I used all the same cylinders and pistons. Despite their age, there were very few miles on them and everything still looked good (to me anyway).

.

if you didn't hone the cylinders then you are taking a chance that the old ring could cut and seal the glazed over cylinders like they would when breaking in a new set of cylinder and piston rings. compression test will show low compression from not sealing and possible a broken ring.

johnnyfresno wrote:

The valves seem to be moving just fine. I pulled of the covers, and hand cranked the engine and all 8 valves moved beautifully.
.

did you gap them to .006? moving beautifully and sealing are too different things. not knowing your VW skills so not to insult but the valves should be adjusted cold (like first thing in the morning cold). also check the valve springs, we have had brought back to life engines break old rusty valve springs.

adjusting valves is the first thing on my tuneup/it don't run list.

1. adjust valves
2. power to the coil and through the distributor and adjust timing
3. are you getting fuel and tune carb.

Mon May 07, 2012 7:38 am

Don't worry, I wont be insulted. My VW skills are much like my skills with the ladys, relatively non-existant. I have been learning as I go, and fortunately, I have a pretty good support group to help me through most things. I did set up the valves properly when I reinstalled them and properly gapped them. I will check and verify the gap today.

Mon May 07, 2012 3:56 pm

Thank you pafree. I went ahead and adjusted my valves. For some reason, they were very snug. After the adjustment, I was able to get it started and running. Now, I just need to do some tuning.

Man, I love helpful people.

Wed May 09, 2012 11:42 am

Way to go , sometimes I have had to readjust my valves a couple of times after the baja has been sitting for awhile then found out that the adjusting screws were too soft and kept hammering themselves into an excessive gap. I then changed them out for the swivle foot scat adjusters and now they run smoother and longer between adjustments. Glad your rail is running again.