Thread: Wash Help!!!
09-08-2007, 03:40 PM #1
Been a while, but finally got back out for an hour today. Ran pretty well except between 2800 and 3800 rpm (blubbery)
Top speed today on the dreamometer wat 51.2
Here is the wash. After 2 hours on teh water after the last rebuild
let me know what you think
09-08-2007, 03:46 PM #2
What are you RPM's?
Year and Model?
09-08-2007, 03:52 PM #3
94 750 SL no mds, other than .50 over pistons on new bore and hone. Mag melted last time out. rehone and new piston 120 Mag, 125 Cen, 125 PTO
Running 93 octane with Pre mix
All screws 1 full out over stock
Repalced Fule line
Cleaned and lubricated Switch
Triple fuel pump
52.1 at 6090 max (seen it once)
mostly 5950-5990 at 49 WOT
Last edited by seaobin; 09-08-2007 at 03:54 PM. Reason: forgot year
09-08-2007, 03:54 PM #4
So no carb cleaning, fuel lines or fuel valve yet?
Stock carb jetting and settings?
How many turns on the high?
09-08-2007, 03:56 PM #5
OOps, I didn't catch your adjustments.
My guess is you're gurgling due to a rich setting in the lows.
Lean with an extra turn out points to fuel supply issue(s).
09-08-2007, 04:03 PM #6
These are general useage shots, not plug chops. This is still just the first 56 hours after rebuild, so I have been going easy on it. Mostly tooling around at about 35MPH (4200 RPM or less) with a few high speed runs thrown in just becasue I am inpatient. So If I was rich on the lows I would think it would show rich after idleing in. I dont know.
I read somewhere that I might need to go up in the jet size when switching to premix?????
09-08-2007, 04:04 PM #7
Is there a way to test fuel pressure out of the pump?
09-08-2007, 04:04 PM #8
Like Al said.... needs more fuel for sure, BUT, I think you're already in trouble.
Am I reading this correct as in these are new pistons?
If so, I think you have some (or had some) foreign debri floating around in there. See pic.... that scares me!!!
09-08-2007, 04:16 PM #9
That was from the first start after I replace the mag piston for the second time. I thought I got it all out (flushed the cylinder with solvent and oiled it down. But after I fired it the fist time, Ran on a hose for 1 minute and pulled the heads again and found a piece of metal (looked like ring material sitting on the top of the piston. 3 little nicks from that. I will probablt replace that piston again over the winter, but I hope it will be fine for now. I know that I got all the pieces of Piston # 2 out now .
Think it will last. i know I read somewhere about deisleing (sp) around high spots on piston or heads. My heads all have spots from where the previous owner blew this engine. I polished them off, but not perfectly. so they will probably need replaced as well
09-08-2007, 04:20 PM #10
Mag Piston # 2 Was Covered Under Theread "piston Damage" About A Month Ago
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