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JB 914
Fired up the car today and it was running really rough. Skline came over and pulled the wires off 1 and 2 and there was no change. Its got hydraulic lifters, could it be they are all collapsed on the one side? It gets gas, and its got spark. I guess the next step would be compression check and pull the vavle cover to see if they are functioning? Any ideas???
DrifterJay
damn...your engine is bad too....... <_<
DrifterJay
at least you got the chevy though...
jimtab
This may sound stupid but pull the valve cover off of the side that's not firing. A VW bug I used to have had exactly the same symptoms and the cause was the bolts had sheared and the rockers were laying in the valve cover, extracted the bolts and re did the job...all better.
Series9
1. Check compression on all cylinders.

2. Use a timing light to verify spark on all cylinders.

3. Check the timing.

Your problem will probably reveal itself in one of these steps.
Aaron Cox
that sucks.....

bummer....was just at joe sharps house, hope it sorts out smile.gif
LvSteveH
If you are running carbs, check the idle jets, they get plugged easily, and can render the cylinder dead until the main jets come on at 3000 rpm, and even then it might be a bit lean without the extra fuel.
skline
I would pull the valve cover off that side and fire it up and make sure your valves are opening. It was working fine before you pulled that cover off earlier, I would bet the whole story will become clear with the cover off. If you were not having that party today, I would have helped you and we could have figured it out in no time. If you do get to it today, let me know what you find? I am still betting either lifters not pumped up or the valve train is not hooked up right. The push rods may be laying in there not even hooked up.
JB 914
QUOTE(skline @ Nov 21 2004, 04:38 PM)
I would pull the valve cover off that side and fire it up and make sure your valves are opening. It was working fine before you pulled that cover off earlier, I would bet the whole story will become clear with the cover off. If you were not having that party today, I would have helped you and we could have figured it out in no time. If you do get to it today, let me know what you find? I am still betting either lifters not pumped up or the valve train is not hooked up right. The push rods may be laying in there not even hooked up.

i popped off the valve cover and it doesn't appear the valves are moving as much as you said they should Scott. i left it off, so, maybe you can stop by on Monday and take a look.

I'm guessing it's the lifters. Anyone got some hydraulic lifters they wanna sell?
Demick
Could be a dropped intake valve seat. Mine exhibited similar simptoms when that happened. If the intake valve seat drops and holds the valve open, then it can affect all of the other cylinders in a very wierd way. I could pull both plug wires from one side of the engine, and both fuel injector wires from the other side of the engine, and it still ran as crappy as when they were all plugged in. Hope it's not that, but a compression test will immediately tell you.

Demick
Dave_Darling
Check all of the wires in the engine bay first. Injector plugs, injector ground wires, and so on. That is probably the easiest way to lose 2 cylinders.

--DD
qa1142
If you are running stock FI the grounds run in pairs side to side. You likely have bank one ground NFG.

Check it.

(Learned this from Brad Mayuer!)
ChrisReale
QUOTE(joe buckle @ Nov 21 2004, 05:13 PM)
Anyone got some hydraulic lifters they wanna sell?

Ask Jake Raby! laugh.gif Sorry couldn't resist
qa1142
Check your grounds
JB 914
running carbs and they are getting fuel
Dave_Darling
Then they're not getting something else, I bet....

You can check to see if they're getting spark by taking a spare plug and taping it so the threaded area (or outer electrode) is against a ground. Then you can watch the plug while someone cranks the starter.

BTW, major compression losses will show up as an uneven pattern in the sound of the starter motor. I found my last dropped valve seat by noticing that the starter went "RR-RR-RR-..-RR-RR-RR-.."

--DD
Aaron Cox
agree.gif check for spark on those two cyls...

then compare that rockers motion with the other like one (exh or intake) on the other side
JB 914
QUOTE(Aaron Cox @ Nov 21 2004, 08:13 PM)
agree.gif check for spark on those two cyls...

then compare that rockers motion with the other like one (exh or intake) on the other side

gonna try that monday if i get time before sundown got dark, so, i closed shop. Cold too!!
JB 914
QUOTE(joe buckle @ Nov 21 2004, 08:17 PM)
QUOTE(Aaron Cox @ Nov 21 2004, 08:13 PM)
agree.gif  check for spark on those two cyls...

then compare that rockers motion with the other like one (exh or intake) on the other side

gonna try that monday if i get time before sundown got dark, so, i closed shop. Cold too!!

BTW, got plenty of spark and gas new plug wires, new points, new pulgs
Aaron Cox
ok..so its strictly mechanical then.... cam - lifter - pushrod - rocker - valve - valve seat pick your poison
skline
The odds of having 2 bad valve seats on the same head which was just done by Rimco less than 1000 miles ago is highly unlikely. We will find out what it is tomorrow and post the results. I am still betting its lifters, either collapsed or broken. It pops on the cylinders when the RPM's go up. See who guesses the resolve. Winner gets a Boobie prize. biggrin.gif
Aaron Cox
loose rockers or bad lifters is my guess...

hows it goin scott?
skline
I aint touching mine again till Friday. Jared said he was going to come out and help me. I have to cut the mounts for the exhaust (Hangers) and then remove the muffler system to get the transmission out so I can make the modification that Renegade said. Should have it out and done in about 3 or 4 hours. Then its time to adjust the clutch and see if it moves on its own. While I am at it, I am going to figure out some way of making the exhaust removable without cutting the hangers again.
JB 914
QUOTE(Aaron Cox @ Nov 21 2004, 08:45 PM)
ok..so its strictly mechanical then.... cam - lifter - pushrod - rocker - valve - valve seat pick your poison

I'm gonna pretend it's the fuel injection problem even though i have Carbs.

let me live in DENIAL at least one more night ohmy.gif
DrifterJay
yeah me 2...hehe... biggrin.gif
DJsRepS
Pull coil wire and turn engin over to hear if it has a dead compression, cylinder if in doupt pull the plugs and use tool. Assumeing it has enough to fire all 4 and you have fuel inj then check the trigger points with ohm meter or pull the dist and clean and inspect and Ohm out with meter anyway. As for your valve motion the best one can do without rebuild is valve adjustment and or pull pushrods inspect for bent. (Slim chance of bent) Also check all grounds at block under intake!!
DJsRepS
Scratch the trigger points I didnt read page 2. Good luck.
JB 914
compression seem pretty low on both cylinders. didn't have time to check the 'good' side

so, it looks like rings headbang.gif headbang.gif headbang.gif headbang.gif

less than 1500 miles. i guess they never seated.

looks like i'm pulling it out and tearing it down again. barf.gif

anyone up for a rebuilding party? i'll smoke some good pork w/ home made BBQ sauce chowtime.gif
Aaron Cox
QUOTE(joe buckle @ Nov 22 2004, 06:36 PM)
compression seem pretty low on both cylinders. didn't have time to check the 'good' side

so, it looks like rings headbang.gif headbang.gif headbang.gif headbang.gif

less than 1500 miles. i guess they never seated.

looks like i'm pulling it out and tearing it down again. barf.gif

anyone up for a rebuilding party? i'll smoke some good pork w/ home made BBQ sauce chowtime.gif

that sucks! you sure the valves are closing all the way?


wacko.gif beerchug.gif
JB 914
QUOTE(Aaron Cox @ Nov 22 2004, 05:38 PM)
QUOTE(joe buckle @ Nov 22 2004, 06:36 PM)
compression seem pretty low on both cylinders.  didn't have time to check the 'good' side

so, it looks like rings headbang.gif  :headbang:  :headbang:  :headbang:

less than 1500 miles.  i guess they never seated.  

looks like i'm pulling it out and tearing it down again.   barf.gif

anyone up for a rebuilding party?  i'll smoke some good pork w/ home made BBQ sauce chowtime.gif

that sucks! you sure the valves are closing all the way?


wacko.gif beerchug.gif

compression held and did not go down, so, i don't think it's valves. it was 75 on one and about 85 on the other one.

i pulled off both valve and they were moving about the same on both sides, so, i'm ruling out lifters.

that compression seems way too low. i thought it should be over 100? i'm not sure what is acceptable.
ematulac
I had the same exact problem when my car sat in storage for a few years.

Remove the top of the carb and check the float and the needle valve.

What I found in mine was that the little wire spring that goes on the end of the needle valve had corroded to gunk and was keeping the needle valve from opening. So basically, the carb was getting gas but the gas wasn't flowing through the carb.

Hope that helps. wink.gif
skline
The gas is flowing through the carb, you can open the throttle plates while its running and watch the fuel flow in, he removed the plugs and they were wet so he is going to pick up some new plugs and try it again. When we pulled the heads off last time I remember noticing there was a lot of deck height (Space between the top of the piston and the head) so I am thinking that is why the compression is so low. If it were mine, I would take the cylinders to Rimco and have about 1/4 inch or so shaved off the top and then replace the rings and lap them in again and run it. I am sure he could take off at leasst 1/4 inch off the top and even still have too much deck height. As I recall, there was about 1/2 inch or so. The guy he bought this engine kit from was building it for a plane so the low compression would be what the guy was shooting for. I would bet the other 2 cylinders are about the same compression.
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