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The timing mark on the underside of my flywheel was off by a fair bit. I thought I was running 25°ish. Once I discovered the error and spent time setting the ignition up I realized it had been running up in the 30° range. Guess my motor has reserves still. I have been leaning it out and do not want that error in there.
I set mine both statically and with a light, unfortunately working alone I could not watch it there was an electronic curve or not.
V6 Yamaha looses a couple at high rpm.
Omc can can gain up to 6 static vs 5000rm under load
I just put a light on it with it running and pull the advance lever forward to the stop and see what it does. I cant see the tach though doing it without someone else but I would say by what I am hearing its dropping a couple degree maybe about 5k rpm.Quote:
Originally Posted by CharlieN
I use a piston stop with a shimmed to stop the piston and about 5 degrees before and after TDC to find true TDC. Insert the stop and turn it clockwise and not how many degrees it stops at. Turn the motor counter and see how many degrees it stops at. Should be the same and if not, adjust your pointed and start over. The piston stop hits square in the middle of the piston so piston rock should not be an issue. Its a lot easier than using a dial indicator IMO.
I just drained from the lower unit. Pressure tested and needed new drive shaft seals. I never noticed but t looks like my drive shaft has been sleeved where the seals ride. I dont see this sleeve on the parts breakdown (its a 1999 115B Inshore case). Cleaned up the sleeve with a little emory and seems good.
The good news is the magnet as pretty clean so I am hoping my new carrier bearing setup is working.
Attachment 306343 Attachment 306344
I wanted to show this little mod that good for about 3-5 psi. I use the Merc slinger washer/grommet and a bead of super weatherstrip adhesive to glue it in place over the water pump. I did this after hooking the hose to my lower one day unmounted and saw how much water is lost there. If you have a straight drive shaft just glue it to the shaft down snug against the pump. If you dont glue it, will get pushed up. If you have a tapered drive shaft like mine, you have to take a little of the flange off the top of the water pump housing to get to enough untapered shaft to glue to.
Also plug the little weep hole in the side of the pump housing.
How much plunge does your input shaft have? The V6 case I run there is a fair amount of end play in the shaft. Why they do not use a thrust collar? I do not think I could get a seal like that to be stable. I have considered machining a retainer and using a conventional lip seal but had just not addressed this yet as to if the pump is drawing in at the shaft or leaking out.
I for one can not close off the little drains and pee holes since we are now below freezing some nights and I will be using the boat for another month. I need the system to drain down.
Quote:
Originally Posted by CharlieN
My seals went bad because when I had the shaft shortened he did it in the case. Said no problem with the seals but he really does mostly Merc stuff and maybe their seal takes the heat better...who knows.
Never had an issue he's done Atleast ten Merc and Omc for me.
If I am correct the Merc shafts get cut and splined where the Yammi shafts need to be welded due to being necked down.
Just assuming since it happened right after is they leaked REALLY bad when I put pressure in the case.Quote:
Originally Posted by baja200merk
PS. a leakdown tester works great for applying low pressure to the case.
None of the merc shafts I see look like they are splined. I cut OMC splines in merc shafts because they are full width from the key way to the powerhead spines and I have a bunch of hacked merc shafts with many different splines laying in the scrap pile.Quote:
Originally Posted by CharlieN
Is it Possible? Absolutely...Quote:
Originally Posted by Mr. Demeanor
I have a Sporty case Beef just finished and when you see the amount of stick TIG'd on this thing you will wonder why all the seals didnt boil and or blow out of it. Pics Tomorrow when its done getting OMC'D.
Leak down tester? You dont like checking it with 175psi shop air and shooting propshaft seals across the shop? :eek: :nonod:
Heck at 175 you might find if the case threads are bad holding the bearing carrier.Quote:
Leak down tester? You dont like checking it with 175psi shop air and shooting propshaft seals across the shop? :eek: :nonod:
I go 10 psi and if it holds that its good. Actually I usually check it with a mighty-vac which is easier and if it fails to hold 10 psi of vacuum, use the leakdown to pressurize it to 10 psi and start spraying soapy water.
After a long time off from doing top end runs I bolted up a 32x15 Performance Propeller ET style today and ran 93mph at 6660 rpm with a full tank, cooler etc. 89 degrees and storms all around us but slick water. Certainly not the best conditions. I plan to put up that 95mph in November at the Suwanee run. Just need a little cool air and a light load.
I only made one top end pass on the lake and could probably have squeaked a little more.
Very nice!
Hell yea that's great. 95 will be a cake walk