Mercruiser 170 with Alpha one outdrive

[gavincollison]

Me and a friend have wanted to buy a boat for a while now.
However we have limited budget, we know that boating is expensive, but we are doing everything as cheap as possible.
We Bought in November (Out of season). It's a 1987 Searay Seville 190BR.
It has a Mercruiser 170 Inboard Engine with an Alpha 1 outdrive.
We purchased the boat for ?1400 with trailer and the engine not working.
I stripped the mercarb down and rebuilt with kit. Engine now runs, yey.
Automatic Choke doesn't work so am going to bolt on a homemade manual choke.
Throttle Housing will not go into foward or reverse gear and can't select throttle only.
Disassembled the Housing and cleaned up. Throttle only now works but still wont go into gear. Have removed Alpha one Outdrive Leg (wanted to check impeller). Gear selection is now ok and the lever in the leg itself is quite stiff but can get it to shift so assuming this is the problem.

Now on to the problem itself. The existing leg had some patchwork on the side (a repair), which I was aware of when purchasing the Boat. The boat came with a spare leg, however he told me that it was for a V6 but that I could simply swap the gearing from one leg to the other. I have to say that I have read the manual and it doesn't sound very simple.

Can I just use the V6 leg on the 170 as is?

The patchwork on the existing leg has broken away slightly. The previous owner informed me that he used it patched up with no problems and bought the V6 leg off ebay at a bargain price as "a just in case".

When I drained oil from the leg it looked good with no water contaminent.

Could I just patch up the old leg again? if so what should I use? And how would I loosen the gearing?

Answer's, Idea's and suggestions are all welcome, Thank you

 

[Bondo]

Re: Mercruiser 170 with Alpha one outdrive

Can I just use the V6 leg on the 170 as is?

Ayuh,.... Welcome Aboard,.... It'll work, but you may, or may not need to change the prop pitch....

Could I just patch up the old leg again?

No idea Where it's broken, so, I can't say....

 

[achris]

Re: Mercruiser 170 with Alpha one outdrive

Some V6s used the same ratio as the 470... Have a look on the port side of the leg and you'll see a serial number. Next to that number will be the ratio. The 470s ran 1.84:1 and the later V6s ran 1.65:1 (earlier one ran 1.84:1). The other thing to check is that the 'other' leg is the same (or earlier) vintage and not a Gen II. If you post up both serial numbers we can check the model and the ratio of each leg..... The serial numbers should start with 0A or 0B and be followed by 6 digits.

Chris.........

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Hi guys thanks for the reply. The damage is on the flat surface of the leg, just under the water inlet but above the propshaft housing. What material would I use to repair this.
The prop doesn't look like the original it's chrome quicksilver.
The boat is being kept in a garage 40 miles away from me but hopefully I'll be going down next week. Can't remember if there's a serial number on it but there's def no ratio printed on it. I found out from these forum's that it's printed on the drive/prop shaft too. Couldn't find that either so assuming that it's too far down the shaft to see when assembled.
Hopefully I can get you the serial number and all will be well.
Thanks
Gav

 

[cr2k]

Re: Mercruiser 170 with Alpha one outdrive

By "leg" do you mean the whole Outdrive or the lower unit.

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Yes I'm referring to the Outdrive Lower Unit. I removed it to inspect the water pump impeller (fried by the way). Also, while i'm on the subject. To remove the rear trim tab on the lower unit I had difficulty. I had a Bolt installed with a normal 6 sided head - not an allen bolt. The access hole for this bolt was smaller than the head of the bolt, no idea how they got it in there never mind tightening it up. I filed the hole back so that it was the same size as the shaft. However still could not get the socket down as to thick. Filed the socket down with a grinder. Managed to get it on but was so thin that the side wall of the socket broke off.
Found a bit of square metal 3/8 tubing. Hammered the end with a large screwdriver to gradually thin the metal and widen the hole. Then found a bolt with same size head and hammered that in to the (now round ended) tube. Simply attatched a 3/8 drive into the other end and presto homemade thin walled socket.

 

[achris]

Re: Mercruiser 170 with Alpha one outdrive

Yes I'm referring to the Outdrive Lower Unit. ....

Generally, 'leg' refers to the complete drive. All lower units have the same ratio. The overall ratio of the leg is determined by the gear tooth count in the UPPER box.... And the lower unit has no serial number on it, or ratio.

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Brilliant. Sorry about the misuse of words. Just to confirm that it wouldn't matter which alpha one outdrive I have ( v6 etc). Any lower unit designed for the alpha one will be exactly the same. They look the same and I just assume the last owner was misinformed about it.
Thank you kindly

 

[vincechig1975]

Re: Mercruiser 170 with Alpha one outdrive

Guys I found ours on the valve cover on a sticker (470) now this doesn't mean they are all like this but willing to bet that might be the first place to start. The engine plate is on the right side in the bottom rear of the engine, sorry to chime in . Learning as I go here as well

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Hi guys, spent all day fitting an exhaust bellow, they are really easy, took 6 hours .
Anyway, I then fitted the new lower unit. I got it fitted and was pumping in the oil bottom up. The propshaft moved out nearly an inch. So that's an inch of play in out. I got my outdrive trimmed up and all of my oil is pooling up in the bottom of the "exhaust chamber". What I mean is that if I look in to the back of the prop I can see my oil. I'm now draining the oil to reuse. That stuffs not cheap. Anyone got any ideas?

 

[Bondo]

Re: Mercruiser 170 with Alpha one outdrive

The propshaft moved out nearly an inch. So that's an inch of play in out. I got my outdrive trimmed up and all of my oil is pooling up in the bottom of the "exhaust chamber". What I mean is that if I look in to the back of the prop I can see my oil.

Ayuh,... The Propshaft should move fore, 'n aft, 'bout 1/8"- 3/16".... Not an Inch...

Obviously, you've got serious outdrive Issues...
Pull it, 'n break it apart,...
Maybe you can see which seal is leakin' oil... it sounds like a Gusher...

 

[Don S]

Re: Mercruiser 170 with Alpha one outdrive

You fill the drive with it down (cavitation plate parallel to the ground). Did you remove the vent plug from the upper while you are trying to fill?

But, even without the filling problem, if the prop shaft moves an inch and the exhaust is filling with gear lube, you have a major problem.

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Well after the initial shock of that I found that the large castle shaped nut was not done up tightly and has no tab washer. Because its a new lower unit i just assumed that it would be good to go, bolt on a prop and off you go. So I need a tab washer and a tool to do up nut. I'm thinking of making the tool. Circular piece of wood with hole in middle and bolts on outside small enough to fit through castle nut gaps. I'll let you know how it goes.

 

[achris]

Re: Mercruiser 170 with Alpha one outdrive

... I'm thinking of making the tool. Circular piece of wood .....

is not going to be strong enough to tighten that cover up to 210ft.lb......

Just buy the right tool and be done with it. They aren't expensive, and you can resell it when you're done, if you want to.

Here on ebay -> http://www.ebay.com/sch/i.html?_fro...l1313&_nkw=91-61069&_sacat=See-All-Categories

Here at iBoats -> http://www.iboats.com/Bearing-Carri...1264953--session_id.355047991--view_id.203934

Chris.......

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Spent all morning making my tool, I have since fitted the castle nut and started pumping in the oil again. All is fine untill roughly a litre has gone in. The oil now comes out of the aft bearing on the propshaft (prop not fitted). Also it feels reaaly tough to put oil in, i noticed this yesterday as well and i'm thinking that I may have a blockage somewhere stopping the oil from getting to the upper unit. When the oil comes out of bearing it does so for small while, i'm pressunig untill pressure reduces. I think this because yesterday when i drained oil it didn't come out very fast (with top vent off), not as fast as when i drained oil to take first lower unit off. I haven't done anything to upper unit so it must be the new lower. Really don't want to take off lower unit again but don't see what choice i have.

Does the oil in the leg sit under much pressure? In other words is this stupid bearing going to leak after i find the blockage and put oil back in?

 

[Bt Doctur]

Re: Mercruiser 170 with Alpha one outdrive

when you replaced the inpeller did you install the seal between the units,called a "quad seal, small O ring looking seal.
there is no pressure in the drive per se.use photobucket and post some pics. the prop carrier must be installed correctly or it leaks,
the prop shaft moving in and out 1 inch is very wrong.

 

[ktbarrentine]

Re: Mercruiser 170 with Alpha one outdrive

Just curious and not getting a clear picture of how you are doing this (adding oil). What are you using to pump the oil in? Do you have the upper plug removed and then fill until oil starts coming out the upper plug port? Did you do a pressure test to around 15PSI before putting oil in the drive?

 

[gavincollison]

Re: Mercruiser 170 with Alpha one outdrive

Installed prop carrier with v at the bottom as that is how it looks in manual. However v is at top on old one. Manual also say's there is a keyway but not one on mine so didn't use that. Now that I have tightened castle nut propshaft only moves in/out 1/8th inch. I'm using the correct oil pump, it screws on to 1 litre bottle and hand pumps.
I've taken the lower unit off and the small oil hole on top was blocked with loads of crap. I've cleaned that out but have also noticed there are oil seals missing at top of driveshaft and back of propshaft. Took the old one off old driveshaft (it's another castle nut with threads on outside, looks like it holds bearing down). New bearing is different to old one as the centre is raised more.
Need to order some more bits now.
For the Driveshaft I believe I need 85040 and 85070 oil seals.
http://www.sterndrive.info/sterndriveparts/mercruiser_parts.html
For the propshaft i think i need 85130 and 85700 oil seals
http://www.sterndrive.info/sterndriveparts/lower_gearcase_parts_drawing.html

They only come as part of a kit and i was looking here
http://shop.tungstenmarine.com/Lower-Gearcase-Seal-Kit-for-Mercruiser-1-R-MR-Alpha-TM2652.htm

I'm going to contact them to see if the seals pictured are the same ones I need

 

[dubs283]

Re: Mercruiser 170 with Alpha one outdrive

Really don't want to take off lower unit again but don't see what choice i have.

that is your only choice

you have to split the drive and teardown and inspect the gearcase internals

 

[ktbarrentine]

Re: Mercruiser 170 with Alpha one outdrive

Just re-read the original post and saw the operative word "cheap"... IMHO, "cheap" boating is an oxymoron... I believe you are in for a long haul with this project, but I am cheering you on and hoping for the best of luck. Keep us posted. It would be great if we could see photos of the problems and the progress. Dont skip the pressure test....