Is there anything up with two of the cylinders on the bottom being lower that the top 4? Rusty, I sent you an e-mail and this was suppose to be on it as well.
Thanks, MT
Is there anything up with two of the cylinders on the bottom being lower that the top 4? Rusty, I sent you an e-mail and this was suppose to be on it as well.
Thanks, MT
How much lower are they reading? If you have lower compression but the cylinders look good, you may need to decarbonize the engine. On the loopers I usually take cold compression and warm compression. These engines like to tighten a bit after warmed up. The lower cylinders will carbon more because the other cylinders exhaust has to pass by it, also they are closer to the water so exhaust pressure is greater here which is why SOME thunder engines have lower compression on the bottom two cylinders. Not all thunder engines have lower compression, this was something they did to aleviate the bass boat shutter in the early 90's. The off shore motors were the same all the way down. Check the compression,but more importantly, check the condition of the cylinder walls. They may just be getting worn. Compare them with the other cylinder walls. Hope this helps you some.
The only problem is this is a motor that has no long been rebuilt. I don't have any problems on high end running, its just on the bottom end it seems a little weak. It never has been a speed demon out of the hole, but I just was wondering if it was the motor or something like to low in the water. Running it on a Javelin 400 TE. Cylinder with a bore scope looks good. The 6 cyl. runns a little lower than the others (10#'s or so diff.)
10lbs isn't much to worry about. Warm it up and see what you get. If it doesn't improve, run decarb thru it,then recheck it.
I have 1996 200 Vindicator. Compression is 120-110 on most, then on #5 its 110 and #6 is 95. How do I decarb piston #6?
Do I spray in the spark plug holes or thru carbs?
Boy did some digging to find that one. Yep shoot thru carbs.
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