67 18hp Fastwin Saga ? (greatest update 7/8)

[Bob_VT]

My new impellar self desructed today. I have never seen one completely destroyed like this? It went from being 6 vanes brand new (2 days ago) to a powder form with 3 pieces I can recognize as vanes.
The remains!!

Inside the aluminum pump housing

I know it will be over a week before I can get a replacement due to the 4th of July (places and shipping being closed)

Any ideas on why? I had the lower unit submerged in a drum of water when I started it?

I have done quite a few over the years and this is the first one I have ever seen turn to dust. I cleaned out the passages, pick up and exhaust and got piles of rubber particles out.

 

[WillyBWright]

Re: Impellar 67 18hp Fastwin Problem

Re: Impellar 67 18hp Fastwin Problem

I'll bet the pump wasn't submerged. That groove worn into the housing would prevent it from sealing well enough to draw water. But if water were in there from being submerged, it should've primed well enough to continue. You need a complete pump.

 

[Bob_VT]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

UPDATE - New impellar and related parts installed (dealer warranted the broken one - it just crumbles in your hand... we actually found another one with the same problem ... BRP quality!!) New one works great.

New problem - Starting.... super hard starting. I had to turn the low speed jet out 8 turns to get it started. Yanked the carb and cleaned it and all the passeges. I have lower than normal compression in the bottom cylinder 100 top 70 lower. When I finally get it running it runs like crap and has to have a high idle. On occasion it feels as if it is picking up a second cylinder. I have been through almost everything (tomorrow I will check the fuel pump).

New coils, condensors, points, plugs, carb gaskets, fuel lines, impellar, and de-carbed.

Very hard starting, no real idle to speak of and rough running when it does run. Point gap is correct, plugs are right.... oh and my arms are tired from all that pulling.

Tips, advice, what am I missing?

 

[tashasdaddy]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

bob it think you are going to have to take care of the compression problem before it's going to run right. pull the head, could be head gasket. the top cylinder is having to drag the bottom.

 

[Bob_VT]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

No mine is not electric start.

Tashadaddy- I was considering a full rebuild and told by the dealer that the parts were NLA. Yes I considered that part of the upper cylinder power was being robbed by the lower one.

I took the carb apart last night and going to start over again today.

 

[Paul Moir]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

Head gasket is still available aftermarket and OEM. Places like seaway marine or stone & sons will often have the NLA parts required for a rebuild, but make sure you really need it first.
A couple stuck rings could also be the cause of the bad compression too. Do a decarb before anything else. If you can draw 3/8" sparks off each spark plug lead, your ignition system is healthy and well timed. Simple, easy test to rule out most problems.
Easy to check the pump too - just unbolt it from the engine, pump the primer and see if any fuel leaks out the back.
If one cylinder is misfiring or running rich it'll affect the compression tests by leaving extra oil in the cylinder.

 

[steelespike]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

You may need new plug wires.You can check each cylinder by simply pulling the plug wires and noting the response.Loosen the wires first and then use insulated pliers to test.You should hear the spark jumping as you move the wires.

 

[Bob_VT]

Re: 67 18hp Fastwin Carb ? Problem (update)

Re: 67 18hp Fastwin Carb ? Problem (update)

Well the pistons are NLA along with a specific bearing. My plan which is already in action is...

Flooded the low compression cylinder with de-carb and letting it set overnight.

The original rings are available (but not oversized ones) and I might get lucky and lightly hone and re-ring if I need to.

Hopefully, I will have accomplished something. Tomorrow will tell and hopefully it is/was a stuck ring.

 

[Bob_VT]

Re: 67 18hp Fastwin Saga ? Problem (update 7/7)

Re: 67 18hp Fastwin Saga ? Problem (update 7/7)

A quick check this morning and the cylinder is still soaking so, the cleaner has not leaked past the rings. I guess I will have some solid results tonight (good ones I hope).

 

[Bob_VT]

Re: 67 18hp Fastwin Saga ? (great update 7/7)

Re: 67 18hp Fastwin Saga ? (great update 7/7)

If I could post a thousand smiles I would

I put the lower cylinder up to TDC and sprayed OMC Tuner (De-carb) in and filled it. I had the motor tilted up so the cylinder was verical. After letting it sit for 22 hours I cleared the fluids and pulled the starter cord about 20 times to make sure it was clear. A quick check of the compression was 100 lbs (up from 70). Now both cylinders are at 100.

Tomorrow I will start it.

 

[RPJS]

Re: 67 18hp Fastwin Saga ? (great update 7/7)

Re: 67 18hp Fastwin Saga ? (great update 7/7)

Nice one Bob, it's great when a plan works in't it.

Just a side thought, you now it's going to be harder work to pull start now you have such good compression.d

 

[Bob_VT]

Re: 67 18hp Fastwin Saga ? (great update 7/7)

Re: 67 18hp Fastwin Saga ? (great update 7/7)

running like a champ! Started first pull and purrrrred!!! A great way to spend a Saturday morning.

Tashedaddy you were right on the money with the compression being so far off. Good Call!

I guess this is testimonial that de-carbing works! I should have photographed the pieces of carbon that came out of the exhaust!!