Drive Pressure/Vacuum Check

Status
Not open for further replies.

brokemerc

Petty Officer 1st Class
Joined
Nov 13, 2007
Messages
233
I have a 1995 bayliner capri, 3.0 alpha1-Gen11... I'm going to try and make up a contraption to perform a pressure check on my drive. I know I saw a post here that had someones pictures of one they had made... Can anyone help me out,, I can't seem to find it. (would this be something that NAPA would carry, they carry all my mercruiser supplies) Thanks..
 
Last edited by a moderator:

Scaaty

Vice Admiral
Joined
May 31, 2004
Messages
5,180
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Yeah, there was a thread on it. I posted a pic of what I made. Let me see if I can find it..
 

brokemerc

Petty Officer 1st Class
Joined
Nov 13, 2007
Messages
233
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Great,, Thanks..
 

brokemerc

Petty Officer 1st Class
Joined
Nov 13, 2007
Messages
233
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Took me about 30 seconds to rig up a vacume tester. I'm assuming that either pressure or vacuume testing is done through either the vent or drain plug hole??? My drive is removed,,, I would think this couldn't be done with the drive installed right? You would loose the pressure through the reservoir.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,931
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Ayuh,..... Off,+ Empty of oil is Best.......
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

not the prettiest, but it works....

attachment.php


i copied this idea from someone else here on iboats.... the connection to the drive is an old style merc gearoil pump made of metal... the connection to the bicycle pump is a tire stem with all the rubber removed so i could put a hose on it... so far, i've done pressure tests with the drive on the boat, off the boat, and seperated in halfs off the boat.... i don't have a reseviour though... surely ya just have to plug it off to do it on the boat for you... don't know that for a fact though since i ain't hip to a resevouir.....
 

Attachments

  • IMG_2848.jpg
    IMG_2848.jpg
    60.7 KB · Views: 48
Last edited by a moderator:

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

I really like that tire valve idea Ziggy. Never would have though of it myself.
No valves, just pressurize, remove pump and the gauge shouldn't drop unless you have a leak. If it drops, get a bottle of soapy water and start checking everything.
 

brokemerc

Petty Officer 1st Class
Joined
Nov 13, 2007
Messages
233
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Yup that's the science project I was thinking about.. Thanks,, I'm still constructing mine, my vacuume tester was easy,, pressure it taking more time.. Thanks...
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

This is my setup...

Single gauge shows pressure and vacuum, and a 1/4 turn valve to close the supply of pressure or vacuum. Threaded metal gearhousing fitting. Easy

:D
DSC03380.jpg
 
Last edited:

starsnstripers

Lieutenant
Joined
Nov 30, 2007
Messages
1,330
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Thats a slick rig too Chris, where did you find a gauge like that? i like that.:cool:
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Any of the auto shops should have them.. They are a 'fuel pump' gauge. Has Pressure and Vac...
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

i see that gage only goes to 11 psi.... i thought ya was supposed to test em to 15 psi? i had trouble findin a gage that had that range which is why i ain't usein my fuel pressure vac. gage.... don't know where i got the one i'm usein. it think it's an old tire pressure gage that i removed the valve from..... what are ya usein for a vac. sorce and pressure sorce?

I really like that tire valve idea Ziggy. Never would have though of it myself.
No valves, just pressurize, remove pump and the gauge shouldn't drop unless you have a leak.
thanks dons. not to often i get to return the many favors you've done for me..... snitchin myself off again though. it was just per chance i used a tire valve. like i said i needed to connect to that chineeze tire pump.... tire valve stem seemed likely. + i was thinkin the vavle would help keep pressure, which it does just like ya say. i can remove the pump after i'm pumped up.. i don't though because the rest of my connections are most suspect.... i'm on my second chineeze pump and all i do is pump up my drive once in a while. pieces of ****.........
 

dcg9381

Petty Officer 1st Class
Joined
Aug 26, 2007
Messages
308
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Anyone know what the thread is on a Bravo-I?
Also - There's an oil reservoir in the motor.. Won't pressure leak out up there?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

Anyone know what the thread is on a Bravo-I?

Exactly the same as the Alpha....


Also - There's an oil reservoir in the motor.. Won't pressure leak out up there?

Test needs to be done with the drive removed. This closes the valve at the front of the drive and allows the drive to be pressured up.

Chris............
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

i see that gage only goes to 11 psi.... i thought ya was supposed to test em to 15 psi? .........

I run the pressure up to just above the 11psi mark... You're looking for a leak, not an absolute value of the pressure applied.
 

alaska_av8r

Petty Officer 2nd Class
Joined
May 28, 2007
Messages
184
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

what are you guys using to pull a vacuum?
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

av8r, that white thing in my pic is a brake system self bleeder tool. it applies vacume... think ya can get them at most autoparts stores...
 

alaska_av8r

Petty Officer 2nd Class
Joined
May 28, 2007
Messages
184
Re: Drive Pressure check--prior post??????

Re: Drive Pressure check--prior post??????

awesome thanks........
 
Status
Not open for further replies.
Top