TOPIC: 1968 Merc 1250 Tower

Hi All,
I am looking for a Tower to play with and have located a 125 Merc from 1968, looks to turn ok and be complete on a quazi abandoned boat. Is this worth looking into or should I run as fast as I can in the other direction?
Thanks
Jesse

I have towers for the 1250 - which do you need: Long or short?
Do you have a lower unit (gear case)??
Depending on where you are located - shipping could certainly kill a deal on these heavy parts and one closer to your home might be worth hunting.
I'm in the state of Washington.
The 1250 is a strong running Merc provided the compression readings are even and it has at least 120 psi minimum on all (6) cylinders.
It is best to limit WOT rpm to 5400-5500 as they work well up to that max.
Some run them harder, but I don't recommend it.
Replacement pistons are NLA so if the compressions aren't good or you open the transfer ports and see the skirts are scratched significantly - you are probably just investing in a dead horse.
Thom

Thank you for the input. I live in NY so I am looking a little closer to home. But I will keep that in mind when looking it over! thanks.
Jesse

Jesse,
I have a good friend in Perry, New York with a HUGE inventory of the older Merc parts and a wealth of knowledge worth seeking out.
Write direct for his information.
frankenmerc at comcast dot net
Thom

Hello,
I did pick up the merc I was after, It was on a 1969 Renken Tri Hull and had two 23 pich two blade brass props with it. I am fairly new to this and I was wondering if these are props you would usually run on a boat like that?
Havent had a chance to work on the engine at all just took it off the boat and braught it home. Boat and trailer are Rough and if any one has interest in either for parts or fix shoot me an email. They are listed in the classifieds. I'd rather send them to people that can use them than fire up the chain saw.
Thanks for any input!
Jesse

the merc crusier pumps are the same but you need to change the 2 hoe to a 3 hose manifold.easier to get.

I am confised I was asking about Propellers on an outboard...
Next Question, Can I use a Pull Pull Cable steering system on the 125 Merc? or will it break pullies etc?

A properly set up cable/pully system can be run on
any outboard. They are still used on many F-1 300hp
raceboats and 500hp Nitros outboard dragboats.

Excelent! thank you for the input!

Hey for what its worth I repowered my 70 Scatcraft from a 40 Evinrude to a 115 Merc and I am using the original pully steering system and it works great.

S: CONGRATS. Merc's always money in the bank going forward. I grew up in your area. NOrth Greenbush (Troy) 12180 area. Frank A, & Brian L have some of these 6 cyl & can advise. Good technical post a few weeks back about the bleed down check valves.

. I would say the 23 " props were too much pitch for a tri hull boat. Just some thing the prior owner got from a seller. Nice for show to polish up . "Chinewalker" up in the 1000 island area, believe had a comment on the older Mercs that Daily use of a heavy brass prop adds vibration to the lower bearing / seals.? May just use for special occasions. The boat should always have interest to local fisherman / teenagers on cheaper budjet. Some other speedster will come along for ya... Not to stir a old pot , BUT if Frank / Brian still have the Custom Craft Manta Ray project hull ,This would make a SWEET show / club package. I had a interest a few years back.

. Maybe a pick up score tomorrow in my state , Barn Find very early Merc Mk 25 Red , E-mail pic recently... 20 yrs ago got a powerhead in Poughkeepsie , & a lower in Finger Lakes region.

Well its been a while but I got the 1250 controlls all rewired with a new ignition switch and finnaly gave it a compression test yesterday 122 PSI -> 125 PSI on all cylinders. Gave it a new waterpump and some paint ( last couple Months) and fired it up. Sprang to life with a nice stron Tell tale and sounded good. ... Painted the lower unit now I need to make the rest match...

Motor is looking good! A curious thing about the 1250's is the WOT timing actually get's slightly retarded if you are not careful how it is set up. 1250 is the only model/year with that linkage to the distributor along with a factory tension spring on the side. So be careful setting it up.
As far as cable steering goes, depending on prop and how much trim/tilt you are going to use the cables may be trouble.
Torque steer can be strong and tilting changes the geometry that may tighten or slacken the cables against the wimpy spring tensioners common on these systems.
DO NOT CONFUSE the cable systems on high HP race or high HP perf applications from your garden variety outboard set up. The race setups that I have seen/have are very high tension on the cables, some inboards are done with turn buckles and are tight like guitar strings no springs at all. The race outboards have the cable connections in line with the pivot point to minimize the length change needed due to trimming they have very high spring tensions, not possible with the coat hanger spring tensioners from years ago.
Personally I think you should go with a push-pull with 125 h.p. but, that is not to say you could not get by with cable/pulley.
My 2 cents.
Godo luck,
Randy

Thank you for the input, I am not sure what system I will end up with on this one but I dont think it will be a cable system I think it will be the push pull or rack off the Renken this came off of. I just think it will be safer than the cables.

Looks like a pretty hefty tri-hull. I'd start with a 19 pitch 3 blade aluminum and take a tach reading at WOT. Looks like a 40 mph rig.

Jesse,
Lower unit came out good. Can't wait to see her all done. I still need to get at my 800. Wife redirected me to laundryroom cupboard building.

Bob

Rattle Can wonder Rustoleum..!.. I hope it holds up ok if not I will get better paint and redo it with my sprayer. too cold out in the barn for that now though..
Now I just need to bite the bullet and get a T&T for it... Not quite ready to undertake that yet..

I have a t/t off of a 78 115 . I don't know if it would work on yours or not. It's on e-bay now and if it doesn't sell we might be able to work something out before I re list it. Joe

Sent you an E-Mail

2 piston that replaces the shocks is the one you need.

Ok this is my first Attempt at a you-tube video or uploading one on here. I am uploading this because I am curious if anyone has an idea why it is blowing a mist of water and oil from the ... Leg? mounts. forward to the transom mount. Otherwise it seems ok, I had too much oil in the mixture for sure having it was the second run after sitting for 10+ years. On the compression test all cylinders were 122 or above. so yeah thats it really... Any ideas on the misting would be great.

There are rubber seals on the upper two mounts. They are old and leaking. You have to pull the power head to get at them. It really does not affect things, but will mess up a clean motor over time.

My 500 merc leaked and it actually affected the idle when I was parked and no wind. The exhaust leaking out the mount would get sucked right back up in the cowl and choke off the motor.

Probably wont happen on a 1250, but food for thought if you ever have idle problems, put a fan on the motor in the shop to blow the fumes away from the cowl.

Conrad

OK thank you for the input! I will leave it be untill further issues occur.

Another Question.. is there too much water coming out of the two holes on the lower cowl? its got a brand new impellor so... My 500 spits some from there but not much The video of the 115 on a different thread doesnt have any water comming out of those holes?