Drive Pressure/Vacuum Check

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brokemerc

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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..
 
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Scaaty

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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

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

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

Great,, Thanks..
 

brokemerc

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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

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

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

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

ziggy

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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.....
 

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Don S

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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

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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

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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
 
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starsnstripers

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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

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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

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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

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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

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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

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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

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

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

what are you guys using to pull a vacuum?
 

ziggy

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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

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

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

awesome thanks........
 
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