SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: BIG JOHNSON on April 28, 2012, 03:38:21 PM
-
140 on 5 cylinders, 125 on two and 145 on the last one checked. That was fully warmed up on the water. Checked all of them twice... Isn't that not good?
Sent from my ADR6400L using Tapatalk 2
-
in all honesty you want all cylinders within 5% of each other. which 2 had 125 , my quess the back 2. in the real world its really not that bad. add a little oil to each cylinder and do it again. like a tea spoon.
-
140 on 5 cylinders, 125 on two and 145 on the last one checked. That was fully warmed up on the water. Checked all of them twice... Isn't that not good?
Sent from my ADR6400L using Tapatalk 2
Did you do the test with the throttle blades WFO?
Seen that bite peeps in the butt more than once. ;)
X2 on a bit of oil, that will tell you cylinder or head.
Also too, were the two low ones the last ones you checked?... And if the boat is running and in the water, WTF are you doing working on it?? :screwy: You should only be wiping down the gel and the new seats with a nice soft towel with a boat soda in the other hand. :beer: 8)
Rookie ;D
GT
-
Did you do the test with the throttle blades WFO?
Seen that bite peeps in the butt more than once. ;)
X2 on a bit of oil, that will tell you cylinder or head.
Also too, were the two low ones the last ones you checked?... And if the boat is running and in the water, WTF are you doing working on it?? :screwy: You should only be wiping down the gel and the new seats with a nice soft towel with a boat soda in the other hand. :beer: 8)
Rookie ;D
GT
Throttle blades shut during test. Probably why it took some cranking each time for needle to reach its max for my recorded numbers.
The two low ones were the two middle cylinders on passenger side. The 145 was the rearmost cyl on passenger side.
Is running very strong, free and handling excellent with the pdc droop and ride plate, its what the boat needed. Oh, and the new bimini looks swell. 8)
Sent from my ADR6400L using Tapatalk 2
-
In theory, if cylinder can't get any air, piston can't move. What diff would throttle blade make?
And if I put a capfull of oil in said cylinders, won't the oil pool against one small portion of cyl wall at top of piston?
If my rings are shot, I won't at all be surprised because since day 1 the fuel pump had been pushing past the needle and warshin the rings put almost constantly.
Sent from my ADR6400L using Tapatalk 2
-
ok heres the reason , well its mostly a theory but everyone follows it. with the butterflies closed it wont draw as much air and since you only crank it over 5 times you as much air as possible to give an accurate reading. look if your worried about your engine and want it tested the best test is a leak down. it will show where your prob is and if you really have one. the compression test is more for a quick look.oh by the way you did have all the plugs out right???
-
Thanks for the info guys. I'm beginning to understand. Just talked to my good buddy mercruiser tech, he says he'd bet dollars to donuts that my exhaust riser on the side with the two center cylinders is leakin water and the valves are screwed.
Edit: he says run it the season, no emergency, and pull heads before thanksgiving turkey.
Sent from my ADR6400L using Tapatalk 2
-
And yes, I started by taking all plugs out.
Plugs looked a healthy light tan Fwiw.
Sent from my ADR6400L using Tapatalk 2
-
Is running very strong, free and handling excellent with the pdc droop and ride plate, its what the boat needed. Oh, and the new bimini looks swell. 8)
Sent from my ADR6400L using Tapatalk 2
then stop focking with it
no misfire, no lack of power, do like gt said and start waxing and drinking :thumbup: its more fun..
just my .02
-
Another .02
Leave it alone and enjoy the boat. I've been around the engine block several times with high performance and the family style boat like you have. I ran a chevy 454 HO with worse numbers than yours for 5 years with no real issues. You can take it apart and freshin it up then really not notice any difference.
Change the oil every season and leave it alone unless you want alot more HP then spend a crap load of money and go all out.
-
I can't stack anymore carnauba wax on it.. gonna fix the leaky riser today, and pull heads after last trip this season.
Sent from my ADR6400L using Tapatalk 2