Pre Alpha 1969 trim having issues going down

[Catfishcabin]

So after picking up my 1969 Starcraft Chieftain 4 weeks ago I finally got all the parts in to get my trim working new lines the switches were badly corroded and rotten so I replace those and everything else seem to find so today I got everything all hooked up filled up system and started testing. Trim up works great flawless trim down begins to work then the pump sounds like it's struggling once it reaches roughly 50% the pump continue to run but the motor no longer drops until I release the switch and then with Gravity Falls the rest of the way? Hopefully somebody out there knows what's going on I worked on it for hours today and couldn't figure it out

 

[Catfishcabin]

Video

https://youtu.be/9-an4BTNB84

 

[Bondo]

Ayuh,.... Yer boat might be a 1969, but the driveline is considerably newer,....

What components are in the trim system, inside the hull,..??
Do the return or Up trim hose, go directly back to the pump, or is there a re4verse lock, 'n trim sender in-line,..??

My guess is, there is a reverse lock, 'n it's not wired properly,...

 

[wahlejim]

That was my thought, Bondo I have an MC-1 trim system and had the same problem. That system has a reverse lock that needs to be adjusted. If gravity is pulling the drive down, I would tackle the seals of the ram as well. $60 kit and about an hour per ram. Make sure you have a torque wrench and follow instructions closely. Another 15-30 minutes to adjust the reverse lock. You can fix the problem for under $100 and less than 3 hours of shop time. Don't know many people who would turn that down.

 

[Catfishcabin]

That was my thought, Bondo I have an MC-1 trim system and had the same problem. That system has a reverse lock that needs to be adjusted. If gravity is pulling the drive down, I would tackle the seals of the ram as well. $60 kit and about an hour per ram. Make sure you have a torque wrench and follow instructions closely. Another 15-30 minutes to adjust the reverse lock. You can fix the problem for under $100 and less than 3 hours of shop time. Don't know many people who would turn that down.

Surprisingly the Rams hold just fine. Would you by chance be able to post a picture of your reverse lock that I'm looking for

 

[wahlejim]

What engine are you running? Odds are it won't be the same. It will be located near the throttle linkage, near where your upper shift cable meets. Need to know the engine, look at the manual, and it will tell you how to adjust properly.

 

[Catfishcabin]

No Title

2.5l 120hp

 

[Bondo]

Ayuh,..... Look in Here,.... Merc Manual #1,.....