Model 75 stuck in gear

Having problems with a Seagull? - ask an expert here

Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo

User avatar
seagull101
Posts: 361
Joined: Mon Jan 23, 2017 10:30 pm
Location: Scottish islands

Model 75 stuck in gear

Postby seagull101 » Fri Aug 04, 2017 11:39 am

Hello everyone,

Got my donor model 75 today!
The only problem is that it is stuck in gear, the bronze 'fork' linkage piece is free and rattles around though!

Any ideas?

Jacob

User avatar
Oyster 49
Posts: 2896
Joined: Tue Oct 26, 2010 6:55 pm
Location: Erfurt, Germany

Re: Model 75 stuck in gear

Postby Oyster 49 » Fri Aug 04, 2017 10:26 pm

Strip it down, clean and inspect, to see what's going on.

User avatar
seagull101
Posts: 361
Joined: Mon Jan 23, 2017 10:30 pm
Location: Scottish islands

Re: Model 75 stuck in gear

Postby seagull101 » Sat Aug 05, 2017 5:29 pm

Yep, the problem turned out to be that the crown wheel was rusted onto the prop shaft, it freed up easy though.

User avatar
Charles uk
Posts: 4260
Joined: Wed Feb 27, 2008 4:38 pm
Location: Maidenhead Berks UK

Re: Model 75 stuck in gear

Postby Charles uk » Sat Aug 05, 2017 6:34 pm

There shouldn't be any water inside that lower unit as it's a sealed unit!
And the crown wheel has a bronze center bush running on a stainless steel prop shaft, so that shouldn't happen.

It might be a good idea to replace both the oil seals with new twin lipped seals, as the original single lipped seals were designed to keep the oil in, not the water out!
Make it idiot proof and someone will make a better idiot.

User avatar
seagull101
Posts: 361
Joined: Mon Jan 23, 2017 10:30 pm
Location: Scottish islands

Re: Model 75 stuck in gear

Postby seagull101 » Sat Aug 05, 2017 7:35 pm

Sorry meant onto the clutch dog and slightly corroded onto the prop shaft!
The gasket that was on it was almost completely gone, i made a new one!

Jacob

User avatar
Charles uk
Posts: 4260
Joined: Wed Feb 27, 2008 4:38 pm
Location: Maidenhead Berks UK

Re: Model 75 stuck in gear

Postby Charles uk » Sat Aug 05, 2017 7:39 pm

Gasket paper 10 thou thick, sorry don't understand clutch dog comment as it's pinned onto the prop shaft.
Make it idiot proof and someone will make a better idiot.

User avatar
seagull101
Posts: 361
Joined: Mon Jan 23, 2017 10:30 pm
Location: Scottish islands

Re: Model 75 stuck in gear

Postby seagull101 » Sat Aug 05, 2017 9:03 pm

I just used a weetabix box for that gasket! I did also use sealant though.
The clutch dog is steel and what i meant is that the steel crown wheel and the steel clutch dog rusted together.
You are definitely right that it leaks because after 5 mins running time the new oil looks horrid!
It also looks like somebody has poorly tried to fix the problem as a home made copper pipe collar was round the bottom of the drive shaft.
You do not have the required permissions to view the files attached to this post.

User avatar
Charles uk
Posts: 4260
Joined: Wed Feb 27, 2008 4:38 pm
Location: Maidenhead Berks UK

Re: Model 75 stuck in gear

Postby Charles uk » Sat Aug 05, 2017 9:24 pm

The thrust washer between the end cap & the crown wheel is there to set the clearance between the crown wheel & the pinion, these washers wear increasing the clearance, using a thicker gasket will add to this as well.

Both of these factors will shorten the life expectancy of your lower unit, & all of these parts are quite expensive except the thrust washers, gaskets & oil seals!
Make it idiot proof and someone will make a better idiot.


Return to “Help”

Who is online

Users browsing this forum: No registered users and 6 guests