Hard starting Yamato 102

[Tom Cronk]

Timing

Every time you move the magneto plate it changes the timing and the points setting,it will move some sideways and up & down.
IT NEEDS to be LOCKED At FULL TIMING, 230 - 250 BTDC.
This will allow best perforance at top end,will still run okay at slow speed and start. BUY SAFTY EQUIPMENT
Tom

[ZUL8TR]

adjustments

Congrads on the work so far. Was wondering how well those pressure feed systems work on the Yamato and your set up works well. Keep us posted on future performance of the pressure feed system. The NGK B10egv plugs without the reducers may be a bit cold for the 14mm heads. The NGK B9EGV might be the way to go since you do alot of mid range running. The NGK PN for the 9's is 5827. Try Advance auto for them that's where I get them.

As far as different plug color have you done a compression test? What are the numbers? In good shape the max with about 4 rope pulls should be about 125 -130. There should be very little difference between cylinders. You might have something with the reeds thought, check the reed openings and set all to spec.

What oil brand and type and oil ratio are you using?

Your rig is low on aero and hydrodynamic lift so to help get farther back and not hug the steering wheel. Once you get used to it and how to set the fin for turns that is the way to go BUT FIRST wear that motorcycle helmet and get a good racing type life jacket.

I don't know if your boat has air traps. If so do they extend all the way to the rear bottom and fade to zero at the end or is there some trap depth at the end. If there is some depth on the traps at the rear that will tend to lift the rear and hold the bow down especially if there is inadaquate aero lift from the deck. No traps will cause air to spill out to soon after the sponsons end and you loose air compression lift on the bottom thus causing the boat to not lift as well.

[BillCNC]

Congrads on the work so far. Was wondering how well those pressure feed systems work on the Yamato and your set up works well. Keep us posted on future performance of the pressure feed system. The NGK B10egv plugs without the reducers may be a bit cold for the 14mm heads. The NGK B9EGV might be the way to go since you do alot of mid range running. The NGK PN for the 9's is 5827. Try Advance auto for them that's where I get them.

Thanks, ...

I really like that fuel pump. So simple and it's nicely made. I wont kid you, ... I struggled at the thought of drilling into the block. Not because of not knowing how, but wondered if it would devalue the engine.

As for the plugs, I can get them from an engine builder I know, ... I'll give him a holler and pick some up. I think the motor was running cold. It never got to warm were you couldn't touch it.

As far as different plug color have you done a compression test? What are the numbers? In good shape the max with about 4 rope pulls should be about 125 -130. There should be very little difference between cylinders. You might have something with the reeds thought, check the reed openings and set all to spec.

No I haven't done a compression check. I'll come home from work a tad bit early tomorrow so I can warm her up before prime time TV so I don't tick off the neighbors.

What oil brand and type and oil ratio are you using?

I bought some Quicksilver PWC 2 stroke oil on the fly and it was the only thing they had. I am mixing it at 25:1

Your rig is low on aero and hydrodynamic lift so to help get farther back and not hug the steering wheel. Once you get used to it and how to set the fin for turns that is the way to go BUT FIRST wear that motorcycle helmet and get a good racing type life jacket.

Oh, ... I learned how to turn her pretty good so far. That's were most of my time has been spent. Is there a difference in helmets between Motorcycle and boating.

I don't know if your boat has air traps. If so do they extend all the way to the rear bottom and fade to zero at the end or is there some trap depth at the end. If there is some depth on the traps at the rear that will tend to lift the rear and hold the bow down especially if there is inadaquate aero lift from the deck. No traps will cause air to spill out to soon after the sponsons end and you loose air compression lift on the bottom thus causing the boat to not lift as well.

Here is a picture of the bottom of the hull while I was painting it.

Thanks
Bill

[ZUL8TR]

comments

The PWC 2 cycle oil you are using is a TC oil as far as I know not recommended for the yamato engine.

http://www.wholesalemarine.com/p/92-...FQ0GnQodrjYAXQ

You need to use a TCW III oil like Quicksilver Premium or Premium Plus (synthetic blend) or others. OK to use 100% synthetic if you want to pay the $$. For your lake use the Premiumj Plus is a good choice I use it in my Y80 and the Merc 25ss for lake running at 16:1. More oil helps the moving parts and seals better.

http://www.boatbandit.com/quicksilve...FQY5nAodnRkAtQ

You have no air traps. Suggest you add them. Details are available if you do this. Easy to do on your bottom to chine design.

Cycle helmet vs boat race helmet not sure? ,but I do know that the cycle helmet will take a hit better than your head. So use it till you find if different than boat helmet . Of course APBA approved helmet would be the final call but you just need protection for lake running.

[BillCNC]

ZUL8TR,

I'll look into swapping out the oil. As far as the traps go, ... were should I look at adding them to an existing hull? I thought these were built into the hull during construction.

[ZUL8TR]

traps

Not on your design. That type construction was used in the 1950's 60's and typical examples are Sid-Son hydros, Swift Hydros and Hal Kelly designs and others. I have a Kelly Wetback that I raced back in the 1970's. Your bottom design is Wetback like. The traps are added after the non trip chines and the bottom are put on. Email Me and I will give you the details with pics on how to do it - real easy if you have a table saw and some basic tools.

[BillCNC]

Email Me and I will give you the details with pics on how to do it - real easy if you have a table saw and some basic tools.

Email sent

[ZUL8TR]

email

Email sent

Email did not come thru? Use:
psushinsky@cfl.rr.com

[BillCNC]

ZUL8TR,

Resent, ...

I guess the one associated with this site is a different email addy.

[3autility]

wetback

I built a Wetback like yours in the 70s and started racing with a 20H popper. People smarter than me pointed out the lack of air traps. I took some pine (I think) and beveled it and tapered it from the sponson to the transom so that it ran to nothing at the transom. Made a difference in how the boat ran. But then I sold that boat and bought a used Bezoats and finally a Giles hydro that I still run the old Mercs on. Those boats were much better than the older Wetback design. As long as you are just a lake racer, you boat will be fine, although probably not as fast as you might like or feel safe with.

[ZUL8TR]

ZUL8TR,

Resent, ...

I guess the one associated with this site is a different email addy.

Who might that be?

[BillCNC]

Who might that be?

ZUL8TR,

The first email I sent you was through this web site. It's set in your User CP.

Anyhow, ... I got the info and pictures. It looks like a very simple mod and I have a ton of Philippine Mahogany I can use for it.
Would it be beneficial to put a small angle (12-22 degrees or so with the inside edge being the high side) to the bottom (not the matting surfaces) of the added pieces? Also, .. how do they act while turning. I was under the impression that the aft end should slide somewhat, but then again, ... what do I know.

Looking at the picture of you on the lake, ... YUP, ... I can clearly see just how far back you are sitting.

I might as well hand myself the infamous Award!!!

One other question, ... What oil should I be using in the gear case?

Regards
Bill

[ZUL8TR]

air traps

Bill

The email address in myCP is the same one I gave you in the previous post. Don't know why it does not work?

I am not following the 12-20 degree angle you are asking about. The rear vertical edge of the traps is what holds in the turn, only minimum side slip wanted. Once set at the rear right trap it acks like a rail with the fin doing holding on the left sponson, takes getting used. Another reason why you sit farther back and set your butt against the right cockpit side in a turn.

Presently using LubriMatic GL5 80w-90 non synthetic gear lube in the Yamato. Just change it regular. If milky looking there is water getting in so seals are leaking at drive shaft and/or at prop shaft. For the synthetic gear lube I use Royal Purple 75W-90 Max Gear in my Merc 25ss. Will use that in the Yamato when the Lubrimatic supply is gone. Other GL5 lubes are out there, Redline makes one so does Amsoil, GL5 is the important spec and low corrosivity which outboard gear lubes have.

Pete

[T Chance]

Another reason to sit back with your hip against the right cockpit side is because if you don't it is going to slam over there anyway and it hurts and turns black and blue.

[BillCNC]

Here is what I was talking about,