Shark will not run over 2500rpm - Update
06-14-2005, 09:52 PM
#31
Scott,
Agree with JP. My 931 had a two pump system which I replaced with a 6.5 bar Pierberg and a 928 intank strainer from 928 Int. Now it often hits the rev limiter a little too fast for this old f@rt.
Dennis
Agree with JP. My 931 had a two pump system which I replaced with a 6.5 bar Pierberg and a 928 intank strainer from 928 Int. Now it often hits the rev limiter a little too fast for this old f@rt.
Dennis
08-08-2005, 12:03 AM
#32
Burning Brakes
Thread Starter
Well, it appears that the solution to the lack of power/sputttering issue was ... drum roll please ... installing a rebuilt fuel distributor.
I ordered a rebuilt unit from 928 intl and installed it over the weekend and the shark runs like a bat out of hell, but not perfect yet. After the install a very noticeable miss is now present at idle. There is no lack of power and she starts better than ever (cold and hot), just this miss and rough idle.
I started trouble shooting after my co and idle had been adjusted. First I began to systematically pull plug wires in an attempt to isolate the issue to a cylinder. With each plug wire removed the idle became worse except when cylinder number 1 wire was removed. After more troubleshooting I was able to determine that the plug wire was ok. Timing is good as well. I removed the plug and it was fouled, very charred and sooty. While the plug was out I installed a compression test gauge just to be sure. compression is ok. I then removed the injector to observ the spray patter. I did so by placing the injector in a clear bottle (while connected to the fuel line), bypassed fuel safety circuit, turned key on the depressed sensor plate slowly. What I observed was this:
- with sensor plate slightly depressed, I could hear fuel flow noise through othe injector lines, but no fuel at this injector.
- depressed sensor a bit more and fuel flow was established, but not atomized spray. More like a lawn sprinkler, about a dozen small streams.
- Only after depressing the sensor half way did the flow atomize.
Seemed to me like this flow is not correct so I removed the fuel line and cleaned and checked for blockage. Re-installed and same issue.
Is this consistent with having a bad injector. Could there be an issue with the rebuilt dist, not enough fuel delivered to cylinder 1 injector?
I ordered a rebuilt unit from 928 intl and installed it over the weekend and the shark runs like a bat out of hell, but not perfect yet. After the install a very noticeable miss is now present at idle. There is no lack of power and she starts better than ever (cold and hot), just this miss and rough idle.
I started trouble shooting after my co and idle had been adjusted. First I began to systematically pull plug wires in an attempt to isolate the issue to a cylinder. With each plug wire removed the idle became worse except when cylinder number 1 wire was removed. After more troubleshooting I was able to determine that the plug wire was ok. Timing is good as well. I removed the plug and it was fouled, very charred and sooty. While the plug was out I installed a compression test gauge just to be sure. compression is ok. I then removed the injector to observ the spray patter. I did so by placing the injector in a clear bottle (while connected to the fuel line), bypassed fuel safety circuit, turned key on the depressed sensor plate slowly. What I observed was this:
- with sensor plate slightly depressed, I could hear fuel flow noise through othe injector lines, but no fuel at this injector.
- depressed sensor a bit more and fuel flow was established, but not atomized spray. More like a lawn sprinkler, about a dozen small streams.
- Only after depressing the sensor half way did the flow atomize.
Seemed to me like this flow is not correct so I removed the fuel line and cleaned and checked for blockage. Re-installed and same issue.
Is this consistent with having a bad injector. Could there be an issue with the rebuilt dist, not enough fuel delivered to cylinder 1 injector?
08-08-2005, 12:58 AM
#33
Rennlist Member
CIS injectors rarely go "bad". I'd recommend you pull them all and get them professionally cleaned & checked.
Also, be careful about how long you let those injectors run... we don't want to see you back here with a "Hydrolocked my engine" post or, if a lot of fuel makes it into the oil, "Spun a rod bearing"
Also, be careful about how long you let those injectors run... we don't want to see you back here with a "Hydrolocked my engine" post or, if a lot of fuel makes it into the oil, "Spun a rod bearing"
08-08-2005, 09:29 AM
#34
Burning Brakes
Thread Starter
Dave,
All of the injectors were replaced about a year ago so I dont expect them to need cleaning. Also, I'm being very careful about flooding the engine. I do not allow the injectors to run for more than a couple of seconds without starting the engine between tests.
All of the injectors were replaced about a year ago so I dont expect them to need cleaning. Also, I'm being very careful about flooding the engine. I do not allow the injectors to run for more than a couple of seconds without starting the engine between tests.
08-08-2005, 10:30 PM
#36
Burning Brakes
Thread Starter
New injector is on the way -- we'll see what happens from here. Anyway....I just got back from a drive. I had almost forgotten how much fun the shark is to drive.
08-27-2005, 08:00 PM
#37
Burning Brakes
Thread Starter
Installed a new injector -- no success. SO, I called the friendly folks at 928 Intl and requested another rebuilt fuel distributor.
I installed the new unit and the shark runs like a top. Special thanks to Jim Baily for all the support.
I installed the new unit and the shark runs like a top. Special thanks to Jim Baily for all the support.
