help with engine running on two cylinders

tim68bug

Hi there,

I was having an issue with spark previously. A friend of mine brought over a different distributor and that end is working fine now. This bug has been sitting for about 7 years. The engine fired right up but only appears to be running on cylinders 3 and 4. Plenty of hot exhaust coming from the left side pipe but just cool air coming from the right exhaust pipe. We checked spark on the wires going to those cylinders and pulled the plugs. Brand new plugs in each cylinder and gaped correctly. We pulled off the valve cover and cranked the engine by hand and just by looking at it while it's turning over all the valves appear to be working fine. There is no strange noise and it doesn't appear to having anything broken. Just appears to be not getting fuel to the right side cylinders and the plugs look clean like it's not burning. Is it possible to get a fuel blockage like that? Any other ideas? Thanks for your help.

DeathTrap · Posted: Tue Apr 10, 2012 3:08 am Post subject:

switch the plug wires around on the side not running

ashman40 · Posted: Tue Apr 10, 2012 4:24 am Post subject:

Compression test?

Did you test the plug wires and plugs outside the cylinders? Use the same wire + plug pairs to see if there is a problem with one of them. Use a battery jumper cable grounded to the frame to hold the metal sides of the spark plugs and crank the engine. You should see a blue/white spark jumping the gaps.

Are you using the technique of removing plug wires from the distributor cap to identify which cylinders are not running? Sometimes cylinder that don't appear to be firing at idle will fire at slightly higher RPMs. Test at 2000rpms.
_________________
AshMan40
---------------------------
'75 Beetle 1200LS (RHD)
"stock" 1600 w/ 34 PICT-3 carb & S/A tranny

andk5591 · Posted: Tue Apr 10, 2012 6:48 am Post subject:

Look for a bad vac leak - like boots on the intake. I assume that you tested for spark on 1 and 2.
_________________
D-Dubya Manx clone - 63 Short pan,1776.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard project at wife's request and your gonna die when you see this one.

v68dub · Posted: Tue Apr 10, 2012 7:47 am Post subject:

Running dual carbs?

ROCKOROD71 · Posted: Tue Apr 10, 2012 8:17 am Post subject:

if there is no spark and gas isn't being combusted in those chambers, then there should be gas collecting/ trickling out the exhaust pipe on that side, no? I might be wrong, but if thats the case and you can't smell/ see gas coming from that side it might be the fuel blockage you were guessing about. Is it dual port? Those have those end casings that connect to the manifold with the rubber boots. Could those boots have disintegrated over the years and caused some plugging? How do the boots look? If your getting spark start inspecting the intake manifold.
_________________
1971 STD BEETLE- 1st car, 1st love. goin for stock!
1977 WESTY "KrustyKamper" 2L FI **de-hippifying process beginning**
***Air Cooled Cruisers Of Central New England***

Listen to the Radiomancy Museum on Tues 5-7pm EST @ www.bostonfreeradio.com and let music find YOU! Sounds you can only hear if you're there!

69 Jim · Posted: Tue Apr 10, 2012 8:36 am Post subject:

tim68bug · Posted: Tue Apr 10, 2012 8:43 am Post subject:

It's just a single carb. I had the thought about the fuel trickling out too if it wasn't burning off but there was nothing. We didn't run it long though since the motor was bouncing around pretty good on the engine mounts. We tested for spark on the two cylinders that don't appear to be firing and they are ok too. A compression test was my next step. There's obviously something going on in the cylinders if cold air is coming out the exhaust so it's getting at least a little compression. At least that's what my rookie know how would think. All the plugs and wires seem to functioning normal but I'm up for any testing so I'll probably switch plug wires around just to see what happens.

69 Jim · Posted: Tue Apr 10, 2012 8:56 am Post subject:

andk5591 · Posted: Tue Apr 10, 2012 10:34 am Post subject:

69 Jim · Posted: Tue Apr 10, 2012 10:36 am Post subject:

tim68bug · Posted: Tue Apr 10, 2012 10:59 am Post subject:

Sorry, didn't mean to be rude if I was. I've never really dealt with any engines before let along vw air cooled stuff. So I'm still really learning as I go and I guarantee I will sound very dumb at times. So I got the timing set a little better and it was running fairly smooth. After I ran it for awhile there was heat coming from the right side exhaust but it wasn't as near as warm as the left side and it seemed to get cooler and then warmer and then back to cool. How does one check for a vac leak? I'm assuming the intake is where the fuel dumps into the cylinders following the line that comes from the carb?

Also, I pulled the plugs while it was running on both 1 and 2 cylinders and it ran about the same. Pulled the plug on #4 and the engine died.

Thanks for the help. Appreciate it.

ROCKOROD71 · Posted: Tue Apr 10, 2012 11:37 am Post subject:

you haven't told us yet if the engine is dual port or single port yet. If its dual port it will have the rubber boots some of us have been describing, they attach to metal "end casings" that look like two tubes welded together that lead to your engine block. get some carb cleaner and spray it around these boots or anywhere else that two parts meet along your intake route to check for air leaks. like where the carb meets the intake, the boots, where the intake meets the engine block. The intake itself could be rusty and have hooles in it. Post pics if you can. Help us help you dude....
_________________
1971 STD BEETLE- 1st car, 1st love. goin for stock!
1977 WESTY "KrustyKamper" 2L FI **de-hippifying process beginning**
***Air Cooled Cruisers Of Central New England***

Listen to the Radiomancy Museum on Tues 5-7pm EST @ www.bostonfreeradio.com and let music find YOU! Sounds you can only hear if you're there!

68IHscout · Posted: Tue Apr 10, 2012 12:24 pm Post subject:

[quote="tim68bug"]It's just a single carb. He did post it,...did you swap the wires on the cool side???

ROCKOROD71 · Posted: Tue Apr 10, 2012 12:31 pm Post subject:

no man, PORT. single or dual PORT. there's a difference on the intake manifold. both types can then have a single or dual CARBS. Whats the engine #? year of car(won't help much but is SOMETHING) doghouse fan shroud? need some CLUES Scoob! Zoinks!
_________________
1971 STD BEETLE- 1st car, 1st love. goin for stock!
1977 WESTY "KrustyKamper" 2L FI **de-hippifying process beginning**
***Air Cooled Cruisers Of Central New England***

Listen to the Radiomancy Museum on Tues 5-7pm EST @ www.bostonfreeradio.com and let music find YOU! Sounds you can only hear if you're there!

68IHscout · Posted: Tue Apr 10, 2012 12:40 pm Post subject:

tim68bug · Posted: Tue Apr 10, 2012 1:25 pm Post subject:

Sorry, it's a single port. Dog house fan shroud. I'm not sure it's the original motor to the car or not, but I believe it is. It's a 1500. Engine number is H5279427. The spark plug in the #2 cylinder looks brand new like it's just been taken out of the box. The #1 cylinder plug looks like it was put in at the same time but has evidence that it's burning gas. There's no evidence that anything is burning in #2. Can't try swapping the wires because the left side ones are too short to reach the right. Plenty of spark on plug wires 1 and 2 though.

andk5591 · Posted: Tue Apr 10, 2012 1:33 pm Post subject:

OK - so lets try this again - get some starter fluid, WD 40 or something and spray around the intake where it bolts to the head. Be careful since these things are flamable. If there is any change in idle speed, you have a vacuum leak. If you do - you can try to gently retorque those nuts. But you will probably need to replace the gaskets. Be careful you dont snap them - and I don't remember the torque spec off the top of my head.

Here's the thing - you could be sucking air into that side and not your air/fuel mix. Would cause your problem.

And here is something else that is possible - you could have something obstructing the manifold (dead mouse, shop rag).

Not grumbling at you - well, yeah I was, but acknowledge a suggestion - as in "don't know how to check for vac leaks". No big deal - we all are still learning. Hope its this simple - and it can be.
_________________
D-Dubya Manx clone - 63 Short pan,1776.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard project at wife's request and your gonna die when you see this one.

tim68bug · Posted: Tue Apr 10, 2012 1:38 pm Post subject:

Thanks,

I'll give your tips a try and report back.

Cusser · Posted: Tue Apr 10, 2012 2:56 pm Post subject:

>Help >Donate >Buy Shirts >Register >Log in	See all Samba banner ads \| Advertise on TheSamba.com

help with engine running on two cylinders
Goto page 1, 2 Next

Forum Index -> Beetle - Late Model/Super - 1968-up		Share:
		Print View

	Forum Index -> Beetle - Late Model/Super - 1968-up	All times are Mountain Standard Time/Pacific Daylight Savings Time Goto page 1, 2 Next
Page 1 of 2