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Monday, October 12, 2015
Friday, October 9, 2015
120-0-30-30
Last week I finally spent some more time on the 72' Super Beetle I bought last year. A few weeks prior I had purchased and received some replacement parts. I bought these parts based on the how the engine seemed to have been behaving.
Basically, the engine would idle acceptably with just a slight burp in it's exhaust note. I thought that since most likely everything on it was probably original and hadn't been repaired much that a good first round of parts to try would a new Carb (34-pic-3), a new Electronic Ignition type distributor, a new 40k volt coil, and a new fuel pump and lastly a new muffler and tail-pipes.
The fuel pressure seemed weak to me so the first thing I replaced was the fuel pump and filter. I installed this and only noticed a slight improvement (VERY slight).
So then I installed the new muffler and tail pipes, as well as the distributor and coil and test drove it. It's NEVER run like a bug should since I bought it. In fact, we've never really driven it aside from back and forth in the driveway and even doing that it seemed super weak.
So I drove it up the street and up a slight incline and it just barely made it up the hill with a fair amount of struggling.
So I replaced the carb. Same thing.
---------------------------------------------
So no I'm thinking... Why didn't I check the engine's compression the very first day. Since a pressure tester costs like $28 at Autozone. Well, I did that, and found the first cylinder had 120 lbs of pressure. This is pretty good for an engine that's been run over 240k miles I thought that was cylinder #2. Then I went to #1 cylinder and found it had ZERO compression. "Well Good" I thought, since that would make complete sense all things noted above considered. The whole time ragging myself for not having checked this FIRST.
Then I tested #3, and #4 and both had 30 lbs of pressure.
Typical pressure on a good beetle engine is roughly 120-150 pounds. Anything less than 90 typically means somethings wrong and needs to be looked at.
So the next day I pulled the engine out and discovered the root(s) of the problem.
After I pulled the heads I could plainly see that #1 cylinder had a cracked and burnt valve.
#3 and #4 both had slightly burnt valves.
Both heads had cracks extending from the spark plug hole to each cylinder.
So the HEADS are trash as far as I'm concerned.
The Cylinders themselves visually seemed ok, and the pistons showed signs of blow-by past the rings.
---------------------------------------------
So...I don't feel like I wasted money on the first round of parts because I would have bought those regardless. So no worries (at least in my mind) on that. And thankfully it's very simple to pull a vw beetle engine and do this sort of checking. Took just a few hours to pull it, and pull the heads off and pistons out. Really not a big deal.
It's a little depressing to find things in such sad shape, but it's also a good feeling to know the reason I couldn't get the new (or the old) carbs to tune properly.
Basically, the engine would idle acceptably with just a slight burp in it's exhaust note. I thought that since most likely everything on it was probably original and hadn't been repaired much that a good first round of parts to try would a new Carb (34-pic-3), a new Electronic Ignition type distributor, a new 40k volt coil, and a new fuel pump and lastly a new muffler and tail-pipes.
The fuel pressure seemed weak to me so the first thing I replaced was the fuel pump and filter. I installed this and only noticed a slight improvement (VERY slight).
So then I installed the new muffler and tail pipes, as well as the distributor and coil and test drove it. It's NEVER run like a bug should since I bought it. In fact, we've never really driven it aside from back and forth in the driveway and even doing that it seemed super weak.
So I drove it up the street and up a slight incline and it just barely made it up the hill with a fair amount of struggling.
So I replaced the carb. Same thing.
---------------------------------------------
So no I'm thinking... Why didn't I check the engine's compression the very first day. Since a pressure tester costs like $28 at Autozone. Well, I did that, and found the first cylinder had 120 lbs of pressure. This is pretty good for an engine that's been run over 240k miles I thought that was cylinder #2. Then I went to #1 cylinder and found it had ZERO compression. "Well Good" I thought, since that would make complete sense all things noted above considered. The whole time ragging myself for not having checked this FIRST.
Then I tested #3, and #4 and both had 30 lbs of pressure.
Typical pressure on a good beetle engine is roughly 120-150 pounds. Anything less than 90 typically means somethings wrong and needs to be looked at.
So the next day I pulled the engine out and discovered the root(s) of the problem.
After I pulled the heads I could plainly see that #1 cylinder had a cracked and burnt valve.
#3 and #4 both had slightly burnt valves.
Both heads had cracks extending from the spark plug hole to each cylinder.
So the HEADS are trash as far as I'm concerned.
The Cylinders themselves visually seemed ok, and the pistons showed signs of blow-by past the rings.
---------------------------------------------
So...I don't feel like I wasted money on the first round of parts because I would have bought those regardless. So no worries (at least in my mind) on that. And thankfully it's very simple to pull a vw beetle engine and do this sort of checking. Took just a few hours to pull it, and pull the heads off and pistons out. Really not a big deal.
It's a little depressing to find things in such sad shape, but it's also a good feeling to know the reason I couldn't get the new (or the old) carbs to tune properly.
Monday, August 24, 2015
Sunday, August 24, 2014
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