power steering line thread size

PowerAddict

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Hi guys,

Does anyone know the thread size for a power steering line?

Its a 1994 mercruiser 7.4 liter. The line comes from the pump and goes to the rack (looking for the side that goes into the rack, not the pump). The thread looks too fine to be regular pipe thread? is it compression fitting thread?

Thanks guys.
 

Bt Doctur

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Re: power steering line thread size

Do you mean the hi pressure or the low pressure side? Hi is from pump to rack, low is from rack to cooler to pump.
 

alldodge

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Re: power steering line thread size

Hi guys,

Does anyone know the thread size for a power steering line?

Its a 1994 mercruiser 7.4 liter. The line comes from the pump and goes to the rack (looking for the side that goes into the rack, not the pump). The thread looks too fine to be regular pipe thread? is it compression fitting thread?

Thanks guys.

Unable to tell you the sizes but if it is to replce without buying Merc, most hydraulic hose shops can make some up. In an old post achris mentions many have gone to the new style using quick connects, just need to find newer modle engine and use parts identified for it.

http://forums.iboats.com/mercruiser...bers-compatibility-power-steering-582184.html
 

PowerAddict

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Re: power steering line thread size

It is the Hi Pressure line.


I don't need a new line, I need a tap for the rack to chase the threads.
 

Bondo

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Re: power steering line thread size

It is the Hi Pressure line.


I don't need a new line, I need a tap for the rack to chase the threads.

Ayuh,.... That Ain't gonna happen,...

It's an inverted flare fittin', pretty much exactly like American automobiles use,...
There's a "Seat" at the bottom, 'n no room for a tap,...
 

PowerAddict

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Re: power steering line thread size

I know what you mean Bond-o. But its' like, the 2nd thread. I'm fairly certain I can get an end-tap in there to get whatever is causing my issue.

I'm fairly certain its a 16 x 1.5 but I can't find any confirmation of that. or a -6an
 

alldodge

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Re: power steering line thread size

How about taking your line to Lowes/Home Depot and see if you can find a nut which will screw on?
 

PowerAddict

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Re: power steering line thread size

well, If I would have been smart enough to take the line off before I left it last week, I would. But, the boat is 64 miles from where I live at farm where I'm working on it, so I don't want to drive all the way out there just to get the line. I'd like to get the tap and then head out there to fix it. Know what I mean? I shoulda taken it off before I left last time - don't know why I didn't. :facepalm:
 

84EdH

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Re: power steering line thread size

I have a high pressure hose for a merc 5.7 that is from a 1995 350 mag alpha. I have no idea if its same size as you need, but I can confirm this:

big end, to the pump, (I presume) is SAE inverted flare 5/8x18, small end to rack SAE inverted flare 7/16X24. maybe you can parts search the hose for your 7.4, and see if it is same number for 5.7 ? hope this helps!
 

PowerAddict

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Re: power steering line thread size

I have a high pressure hose for a merc 5.7 that is from a 1995 350 mag alpha. I have no idea if its same size as you need, but I can confirm this:

big end, to the pump, (I presume) is SAE inverted flare 5/8x18, small end to rack SAE inverted flare 7/16X24. maybe you can parts search the hose for your 7.4, and see if it is same number for 5.7 ? hope this helps!

AWESOME! Thanks, I'll check!
 

alldodge

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Re: power steering line thread size

Could not find the size anywhere. Only found that the Merc fitting is propritary for the quick connects, and the same ram is used on about all boats these days. I have an old ram in my shop with quick connects which I used a dial caliper on the threads and eye balled the threads.

Small
0.5121 (13mm) by 24 threads per inch
Large
0.6230 (15.8mm) by 17 (could be 18) threads per inch
 

Bt Doctur

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Re: power steering line thread size

Before you go crazy, I might have the fittings from an old hose or someone here might have a bad hose that you could remove the fitting,
file in 4 slots to act as cutters and thread that in to chase the thread.
 

Bondo

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Re: power steering line thread size

Before you go crazy, I might have the fittings from an old hose or someone here might have a bad hose that you could remove the fitting,
file in 4 slots to act as cutters and thread that in to chase the thread.

Ayuh,... Or he could go to an Automotive Parts House, 'n buy a brake line fittin', 'n do that,...
 

PowerAddict

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Re: power steering line thread size

I just want to say I think its pretty awesome you guys are trying so hard to help me with this problem. I do hope one day there's something that I can contribute for you all.

What do you mean my file 4 slots? like, flat spots on the threads? Every 90 degeres?
 

Volphin

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Re: power steering line thread size

You might try a thread file if you can find one...
 

Bondo

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Re: power steering line thread size

I just want to say I think its pretty awesome you guys are trying so hard to help me with this problem. I do hope one day there's something that I can contribute for you all.

What do you mean my file 4 slots? like, flat spots on the threads? Every 90 degeres?

Ayuh,.... Turn the fittin' into a tap/ thread chaser,...
 

PowerAddict

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Re: power steering line thread size

Just so everyone knows It was a 14 x 1.25 (Metric!) I actually found a tap for it too and was able to get the fitting in. Thanks everyone.
 

Volphin

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Re: power steering line thread size

Great job! And thanks for posting the size! Someone, someday will need it I'm sure.
 
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