Help! P-29 dies when put into gear??
#31
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Does it die instantly when going into gear or does it struggle at all then die? You can safely bump the RPM as a test. carefully bump it to 800-900 RPM and see if it does the same thing.
IAC or possibly a vacuum leak are the obvious culprits.
IAC or possibly a vacuum leak are the obvious culprits.
#32
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Yes sir that is correct. I have not seen or touched a Blackhawk drive app in years. For some reason I thought a fully warmed up MPI with a BLACKHAWK app was idle min at 650 to 700 RPM's.
I went to look back in my service notes and it was listed for bravo and Blackhawk apps a 350 MPI should have an idle of 600 rpms. SO MY BAD. I POSTED INCORRECT INFO.
With that said somehow I could of sworn that idle with MPI engine and Blackhawk app was 700 rpms / 650 rpms bare min.. If I ever find that info and what app w/ Blackhawk that applies to, I will post it. But again I still might be totally wrong.
I went to look back in my service notes and it was listed for bravo and Blackhawk apps a 350 MPI should have an idle of 600 rpms. SO MY BAD. I POSTED INCORRECT INFO.
With that said somehow I could of sworn that idle with MPI engine and Blackhawk app was 700 rpms / 650 rpms bare min.. If I ever find that info and what app w/ Blackhawk that applies to, I will post it. But again I still might be totally wrong.
This was running on the hose with no props installed. What's interesting is I put them in gear, both forward and reverse, and for a brief moment during shifting the engines they would drop to 500 rpm then go back to 600 rpm (according to the SC5000 digital tach). Engines sound and run perfect and no sign of dying during the shift. I even saw it drop to 450 rpm once. The cam in these engines is sooo mild. Just another observation.
#33
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Location: Rolla/LOTO MO
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Update: I've been traveling with the MTI BatBoat attending the OPA races and haven't had much time to spend with the P-29. So this is where I'm at with it, did find the props were out of time, fixed that still dying. We put new IACs both motors cleaned the throttle bodies still dies. I've run about 300gal threw it everything is great but dying when put into gear. Someone mentioned to me that the motors are tired, but it was fine before we pulled them. They don't smoke don't use oil the oil is still clean. Fires right up and sounds strong. Motors have around 440hrs. It still runs 74mph with two guys cooler 1/4 tank and all the other junk in the boat. 76.6mph is what Power Boat Mag ran it in 1996. I'm trying to find my water ears now to try in on the trailer.
#37
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Actually my point of jest was to add Blowers and then shift during the "up surge". Sometimes laughter isn't the best medicine..
Not familiar with the MPI engines but do they have a distributor? If so could the advance plate/springs be broken and the bump of going into gear wacks out the timing killing the motor? Used to have an older chevy engine that would run perfect other than the occasional stall or backfire (which was bad enough to blow off all vacuum lines) and after many hours found a broken piece on the advance mechanism.
Not familiar with the MPI engines but do they have a distributor? If so could the advance plate/springs be broken and the bump of going into gear wacks out the timing killing the motor? Used to have an older chevy engine that would run perfect other than the occasional stall or backfire (which was bad enough to blow off all vacuum lines) and after many hours found a broken piece on the advance mechanism.
#40
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I put water ears on the trailer today and gave them both a try. When you put both of them in gear there is NO rise in RPM. They both drop about 20RPM then back to 600RPM, there's no way you will kill it on the trailer.