C40TLRX lost #2 Cylinder

[99yam40]

Last Wed I was heading down the intercoastal canal running about 5K RPM and things went south.
loud noises and then just some tapping.
Dropped RPM to 2K & turned around headed back to bout ramp.
once across the cut to the gulf it got loud again so I shut it down and push poled back to the ramp along the edge of the canal.

Pieces of ring and piston missing on exhaust port side of cylinder #2.
head beat up and piston has pieces inbedded in it.
cylinder is scored up in the area


Due to the welding and Epoxy putty I have used in the past to keep this motor going I am not planning on boring or resleeving.
Not finding rebuilt 40s or used good blocks ,I am thinking about putting a new F40 on my 16ft Express.
waiting on a reply from the local Yamaha dealer on cost, but found on this web site the F40 would be around $6K.
If I bought on the web, how would the warranty work if I installed it myself?

Do I have to have a local dealer do the install?

will the old 703 controls work with the new F40, or will that all need to be replaced also?
Not sure if the old control wiring would plug into the new F40 or the throttle and shift cables work properly.
fairly sure the steering Should work.
But not positive about that either.
Any info on this would be appreciated

[ausnoelm]

New motor, use new control and wiring, why spend lots on a motor then try to root around with old wiring?

[99yam40]

OK let me ask that in a different way does the New F40LA have 10 pin harness connector or a 7 pin.?

[panasonic]

I think you will be happy with a new four stroke..if for any reason that it is quiet!

[robert graham]

Sorry to hear about your engine failure….If this was me, I’d be searching for another motor very similar in year, HP, etc….that is still running…..then you can use your old broken motor for extra parts. Someone, somewhere must have an old C40 laying around…..maybe with a broke lower unit or similar that would make it very affordable…..just an idea…
Again, sorry for your bad luck!!….Robert Graham

[99yam40]

that is what I have been lookiing for, but not finding any
even looking for a good or rebuilt head, with no luck.
Not sure if ordering a new crankcase assembly will come with the head. or what would fit properly do to the original part number is no longer available

one of my sons found a 1989 pro 50 for $2k,
but I do not think much from my 1999 C40 would interchange and I have no idea what kind of shape it is in

[99yam40]

got a call from the local Yahmaha dealer.
said the F40 would be 7300 and a F50 7800.
350 for a new con*****er for the new motor and was not sure how much the install would cost, depending on what all they had to do.

being a old time do it your self guy, what would happen if I bought the motor on here and installed it myself.
how would the delivery and warranty work?
can save some money.

[panasonic]

I am no help with the install and warranty business...cause I never bought a new one.

Have you looked around for a used one a few years old with low hours?

[99yam40]

I have been looking for a block or motor that would fit my 99 C40TLRX so I have spare parts that I could use.
have not looked to a 4 stroke yet, just the only thing I can find new now a days.

I may still look for a machine shop that could punch out my block to see how much that will cost.
just to bet that the block might hold up for some years.
heck I am turning 71 this year, so how long do I need it to last?

[pstephens46]

[QUOTE=99yam40;n239206]got a call from the local Yahmaha dealer.
said the F40 would be 7300 and a F50 7800.
350 for a new con*****er for the new motor and was not sure how much the install would cost, depending on what all they had to do.

being a old time do it your self guy, what would happen if I bought the motor on here and installed it myself.
how would the delivery and warranty work?
can save some money.


I called the Yamaha USA office in Kennesaw Ga about 10 years ago and got a good bit of information. Why not give them a call with the warranty questions? Dealers can be shady IMO. I know of a few that told customers that DIY oil changes would void the warranty. I later found out that is not the case. Where is Boscoe???

[99yam40]

I found a 1999 40 on ebay supposedly in good shape 130 on all Cylinders.
buy it now was 3790 I offered 2750 and they are shipping it to me tomorrow.
with taxes and shipping it is still way above 3500.
But all my parts should fit it if needed.
I just finished disconnecting everything on mine so it is ready to pull/
We shall see if this was a bad idea or not before long.

I still remember outboards costing about $100 per HP not that long ago(at least it seems not long ago).
I just cannot bring myself to spend 8 to10 K on a 40/50hp motor

[99yam40]

well, the motor showed up yesterday afternoon,
so I picked it up from the place I had it shipped to and figured out how to get it off the pallet and into the air from the back of my truck.
hung it on the back of my boat and hooked everything up by 7pm last night.
today I dropped the lower unit and found out the 5th bolt(under the tab zinc) was missing.
hole is missing threads, but If I can find a longer bolt there are good threads in there deeper.
Ran a compression check and all 3 were at 117psi.
the full retarded stopper screw is run all the way down for some reason.
fired it up and timing was off and idle was very high.
adjusted the timing using a timing light to 7 ATDC had to adjust the link, and backed off the idle speed screw to get down to 800RPM out of the water.
Disconnected the linkage and moved the CDI wiper to the full advance mark while at idle (where it sits normally at open throttle) and it checked out 25BTDC with my timing light.
Put it into the water and ran it up and down the bayou at 4300 and them at 5200 for 15 to 20 minutes, twice and it seems to run well with no overheats and other problems.
I had put my old lower unit on there for testing since it had the Stingray foil attached already
motor would jump up and run to 6000 if you let it like my old motor would with that prop I had on it.

I will try the prop that came with the motor to see what that does eventually, but I wanted to make sure the prop I had on the old would still do the same on the new motor as it did before.

I may still put the CDI from my old motor on with all the other linkages to see what is going on with the stop screw run in so far.
see if I can get the linkages all back to spec.

so far so good.

Oh yea, when I got home from running the boat I ran another compression check and all 3 were at 110psi with the motor warm to touch, but not full warmed up to operating temp

[99yam40]

I swapped out the CDI from my other motor, and that fixed the timing issue .
It was the same problem I had with my original Motor years ago, timing too far retarded at idle so others jacked with everything to make it run but not well
took some playing with to get all readjusted.
carbs pilot screws were 3 turns out, instead of 1 1/2 turns,
Idle speed screw was holding the carbs open too far,
link and synced the carbs
timing marked on CDI and wiper/pointer are all back in spec, even the pick up of the roller to start advancing the timing is back in spec.
ran a shock dose of Ring free plus into the motor while I was adjusting everything.
I will let it sit overnight and take it out again on the water tomorrow or the next day.
I will take the prop that came with this used motor with me and try it out to see how the boat handles it too.

[mjm-1957]

Glad it all worked out for you.

[99yam40]

took the prop off the lower that came with the motor and it is a 11.75 X 17.
the one I have been using is a 10 1/8 X 13

I have a feeling going up in diameter and pitch that much will not workout.
we shall see.
going fishing in the morning, but not sure I will try the other prop,
too dang hot to fool around long out there right now after things heat up