Replacing lift cyl power trim hose,how much heat to use?

[crazy charlie]

1988 Mercruiser alpha .I have a slight leak in one of the lines.Not sure if the lines have ever been changed.Boat sits in salt water 5 month of the year so i am assuming the line is not coming off easy from bottom of transom assembly and dont want to damage anything.Plan on using a brake line wrench after using some Map torch heat.How much heat is too much heat on this? Any tips to make this go easier would be appreciated.Charlie

 

[Scott06]

1988 Mercruiser alpha .I have a slight leak in one of the lines.Not sure if the lines have ever been changed.Boat sits in salt water 5 month of the year so i am assuming the line is not coming off easy from bottom of transom assembly and dont want to damage anything.Plan on using a brake line wrench after using some Map torch heat.How much heat is too much heat on this? Any tips to make this go easier would be appreciated.Charlie

You may need some good heat and some Kroil or other goo penetrating oil applied days before hand. you also can cut the line to get a box wrench on it

 

[crazy charlie]

Thanks ,what I am trying to determine is how much heat??? I have concerns heating the aluminum.Map is what I have usually used.Charlie

 

[alldodge]

The manifold is aluminum and maybe what is actually causing the leak, but time will tell once apart. Removing the manifold will allow the heating to be done faster (less heat sinking) but then you have an issue of the gasket. I might try a heat gun before Map

 

[Scott06]

Thanks ,what I am trying to determine is how much heat??? I have concerns heating the aluminum.Map is what I have usually used.Charlie

I know but how do you quantify that??? Mapp or propane is fine. Start with a little try to get it off, add more if needed. Aluminum doesn't take much to expand.

As mentioned if you are concerned try a heat gun first. Probably 150-180 F will do it? This is just based off of using a bearing to get press fit bearing on shafts.

 

[Bondo]

How much heat is too much heat on this?

Ayuh,..... Aluminum melts at 'bout 1200°, so less that that,.....
'n I agree, pull the manifold down 1st,.....

 

[crazy charlie]

Ayuh,..... Aluminum melts at 'bout 1200°, so less that that,.....
'n I agree, pull the manifold down 1st,.....

ok 2 things......1st I didnt realize that it was a seperate manifold under the housing. 2nd if I am able to drop the manifold ,Wont that make it harder to get any leverage to get that old line off??

 

[crazy charlie]

BTW the leak is def in the line and not in the manifold.

 

[Bondo]

ok 2 things......1st I didnt realize that it was a seperate manifold under the housing. 2nd if I am able to drop the manifold ,Wont that make it harder to get any leverage to get that old line off??

Ayuh,....... It's held on with 2, 1/4" bolts, up from the bottom,.....
I'd be concerned by excess heat in the transom housing, as a mapp torch isn't really a concentrated flame,.....
If holding the manifold with a crescent wrench don't work for ya, screw the bolts back in, after you do the heat, 'n oil it up thing,.....

 

[crazy charlie]

Ayuh,....... It's held on with 2, 1/4" bolts, up from the bottom,.....
I'd be concerned by excess heat in the transom housing, as a mapp torch isn't really a concentrated flame,.....
If holding the manifold with a crescent wrench don't work for ya, screw the bolts back in, after you do the heat, 'n oil it up thing,.....

Thanks will give it a closer look.Using a 3/8 brake line wrench ,there seemed to be a little play when fitting it onto the the line.Should i get a metric for this?

 

[Bondo]

Thanks will give it a closer look.Using a 3/8 brake line wrench ,there seemed to be a little play when fitting it onto the the line.Should i get a metric for this?

Nope, it's 3/8",....

 

[crazy charlie]

Nope, it's 3/8",....

thanks,maybe just a better quality brake line wrench???

 

[04fxdwgi25]

A little suggestion: if heating a hydraulic line, disconnect one end so the expanding fluid has somewhere to go. Have seen those lines rupture, sometime in a violent fashion, when heated and sealed at both ends.

 

[Alumarine]

thanks,maybe just a better quality brake line wrench???

A name brand wrench would be best but there will always be a bit of play.
If you have room you could use a pair of vice grips to close the wrench to reduce play.
Like Scott06 said, if it's the line why not cut it and use a box end wrench?

 

[crazy charlie]

A little suggestion: if heating a hydraulic line, disconnect one end so the expanding fluid has somewhere to go. Have seen those lines rupture, sometime in a violent fashion, when heated and sealed at both ends.

I assume removing the cap off of the resevior would safegard that.I am planning on using less heat after Bondos info.Maybe regular propane instead of the yellow can.Charlie

 

[crazy charlie]

A name brand wrench would be best but there will always be a bit of play.
If you have room you could use a pair of vice grips to close the wrench to reduce play.
Like Scott06 said, if it's the line why not cut it and use a box end wrench?

makes sense ,but I think I would use a socket before a box wrench...right??

 

[crazy charlie]

anyway, been spraying Pb blaster for a few days though I have no confidence any of those penetrants work unless it is a rusted nut/bolt that you can have gravity assist in the penetrating.I have had zero success with any nbrand working on anything marine.Charlie

 

[Scott06]

anyway, been spraying Pb blaster for a few days though I have no confidence any of those penetrants work unless it is a rusted nut/bolt that you can have gravity assist in the penetrating.I have had zero success with any nbrand working on anything marine.Charlie

try Kroil, if you havent. It is expensive but if you work on boats and old cars it is the best I have seen.

 

[04fxdwgi25]

I assume removing the cap off of the resevior would safegard that.I am planning on using less heat after Bondos info.Maybe regular propane instead of the yellow can.Charlie

I don't think so. Those lines are closed off via valves in the pump. If not, the pistons wouldn't lock in position.

The tank cap only closes off the "no pressure" tank that feeds the pump / control valves.

 

[crazy charlie]

SURPRISE,SURPRISE......after spraying PB blaster for a few days ,the line connections came off quite easily with no heat attempted at all.Should I be eating my words having no confidence in penetrants??? Anyway all loose and all good. I have 2 donor cylinders ,one with a braided ss covered line and one with without a ss cover....SS covered line is not coming off and non ss covered line came off easily.Planning on using that line unless the local supplier has an ss covered line in stock. Regular non covered line should be fine I assume??? Charlie