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I saw previous posts about not running an engine out of water. If I disconnect the driveshaft can I set the idle mixture and timing without problems? How much does a jet drive load up an engine? Is it like an auto transmission or worse? What temperatures do you guys prefer on moderate BB Chevrolet engines?
STANDARD, I RUN MY ENGINE OUT OF WATER TO SET TIMING AND MIXTURE. I DON'T THINK A PUMP PUTS TO MUCH OF A LOAD ON ENGINE. YOU CAN USUALLY TURN PUMP BY HAND CAUSE IT DOESN'T HAVE ALOT OF MOVING PARTS LIKE A AUTO TRANS/GEAR BOX THAT HAS ALOT OF DRAG. I SET MY TIMING AT FULL ADVANCE BETWEEN 33-36 DEG. ADVANCE AT 3200 RPM. MIXTURE IS TUFF TO SET OUT OF WATER. INITIALLY I WOULD SET MIXTURE TO 1-1.5 TURNS OUT, THIS WILL CHANGE WHEN ENGINE HAS A LOAD ON IT WHEN IT'S IN WATER. ALWAYS CHECK IT AFTER A HARD RUN, PULL A COUPLE PLUGS AND GO FROM THE READINGS. USUALLY YOU WANT THE PLUG TO BE A MED. TO DARK TAN COLOR. WHITE IS LEAN AND BLACK IF RICH. I USUALLY RUN MY TEMP AT 150-180 DEG. BUT TO EACH IS THEIR OWN. HOPE THIS HELPS
You can run your motor on the trailer with the pump disconnected and water supplied to the motor and get a base line. This will get you started as far as setting your timing and some adjustment to your carb. But on the contrary to what was said before your pump puts alot more load on your motor that you think. Just because you can turn it by hand freely try turning it in water. A good example is set your motor to idel where you want it to without the pump connected and then with it connected put it in the water you will probably loose about 200-300rpm guessing so yeah it will put quit a bit of load on it. But as far as setting the timing I preset mine on the trailer all the time.
-Later-
HEY STANDARD MAYBE I PUT IT THE WRONG WAY CAUSE SOMEONE ELSE DIDN'T UNDERSTAND. YES YOUR PUMP WILL PUT ALOT OF LOAD ON ENGINE IN THE WATER, BUT OUT OF WATER IT HAS VERY LITTLE LOAD ON ENGINE. YOU CAN SET YOUR ENGINE UP ON TRAILER BUT FOR SURE THE MIXTURE WILL NEED TO BE RE-DONE IN THE WATER CAUSE ENGINE WILL NEED MORE FUEL WITH A LOAD IN WATER THEN WITH OUT. I KNOW MY ENGINE WILL TWIST 6500RPM OUT OF WATER BUT ONLY TURNS 5000 IN THE WATER, A LITTLE MORE THEN 200-300RPM DROP http://free.***boat.net/ubb/smile.gif
if it only twist 6500 out of the the water, I would say you'r valves are floating. if it twist 5000 on the water could be the the PFD's are draging instead of floating. I would check the kick down linkage on the down rigger......
...Could be the caps lock button...
Thank you again guys. And Froggystyle I'd still like to check out the factory (if the offer still stands).
HAVINAFIT, Im sure it will rev higher, i don't hold it open, 6500rpm is just a quick rap of throttle. Tach only goes to 7000, I know it doesn't float valves. Why don't you rev yours that high on trailer and hold it and let me know what happens. http://free.***boat.net/ubb/smile.gif
When I say a 200-300rpm drop I mean at a idle, anyone who wings there motor to 7000 on the trailer is just asking for trouble.
I'd like to come watch that high revvin test on the trailer. I'll be the one behind the safety wall.