Oil Cooler Lines

[tomtom72]

Hi guys,
I think I have an oil leak from the oil lines. I know I heard that this is a common problem, or at least I think I heard it? They are not leaking at the motor end or the cooler end but at the rubber/metal transition point. Is that the common place for them to leak?

I tried over at the registry site to see if anything was noted on this subject. I guess I'm just trying to figure out why the leak happens at all at the spot where I see mine leaking. I ran the P/N and it seems this is one part the General still sells for our cars. I would be open to any suggestions on better replacement parts if anybody knows of a source that makes better lines.

Thanks a bunch!:thumbsup:
Tom

[Aurora40]

Hmm, I notice a few drops on the garage floor now and then from where the lines/cooler is. I haven't really gotten around to investigating it, though. If it's where rubber meets metal, like at a permanent crimp, I'd think you'd need to replace the line.

Keep us/me posted as I'll probably need the same info when I look at mine! :)

[1990 quasar blue]

http://www.zr1netregistry.com/ZR1_issues.htm#16

Is there a chance that it's running down from another spot? Maybe try cleaning it up and keep an eye on it to see if thats where it originates.
Good luck,
Mike

[tomtom72]

Hi Bob & Mike,

Bob I noticed the oil as a wet spot on the frame rail directly under the transition point when I was cleaning up under the hood. The spot was not there the last time I detailed the motor. The first thought I had was that it could be the A/C lines, as they are directly under the oil lines at this point. Yes I'm gonna watch it & I'll post up if I can actually see anything. I'm gonna use some de-greaser to clean up the mess well so I'll know for sure if the lines are leaking at that point, either set as they're both over the same stain.

Thanks Mike, I had looked at that notice and I figure when I do my cooling hoses I'm gonna give that side of the lines a good eyeball to see what's up at the motor end of them. When I noticed the stain on the frame rail I didn't have my telescoping mirror & a flashlight with me so I couldn't see much. The light in my rented garage isn't good enough for that kind of situation.

On the bright side P & G Chevy says the P/N on the lines is a good P/N, and only $99.00 + $0.79 x 2 + shipping!
:cheers:
Tom

[Tom]

The common leak is at the crimp joint. The new GM hoses will look different and are supposedly an improvement over the original 90 hoses. My original hoses went a long time before they started leaking.

[tomtom72]

Tom, Thank you for the info. It seemed to me that after reading the stuff over at the netreg site and looking at my particular situation that my symptoms were different. The thought had occured to me that the crimp point would be the most likely trouble spot if there was to be a trouble spot. I guess it would have been too much to ask for S/S braided lines on a 60K car. They sure would look nice, though.

Thanks for your time!:thumbsup:

:cheers:
Tom

[ralph92ZR1]

Tom,
Got my 92 z last March. Did the oil cooler lines in April. Pretty straightforward. See the article in the registry by Rob Loszewski [April 29, 2005]. Only took about an hour and no more leaks. Parts cost $139 from Stoudt Auto sales. Watch for the washers and only snug up at the oil cooler fittings.
Good luck!

[tomtom72]

Hi Ralph,
Thanks for the input! Yes, I looked at the write up by Rob L over at the netreg site when I was trying to find info on my situation. It does seem a straight foward job. I'm gonna order up the parts & get'r'dunn as soon as I can. I just have to wait for my credit card to cool off a bit!:o

:thumbsup:
Tom

[Aurora40]

Looks like mine need replacements too. The lower hose is leaking from the crimp up near the cooler.

The write-up on the registry says to drain the oil. Mine's about 200 miles old, is this really necessary? I wouldn't think the engine is so full that it is full up to the cooler lines.

Tom, what was the best price you found? It's $107 with shipping from GMPartsDirect.

[tomtom72]

Bob I ordered mine from P&G and the parts total was 101.57 + shipping...I figure 10 bucks or so as they use brown & they're cheap. I'm developing a relationship with those guys!:sign10:

I saw the same article by Rob L as you did...I'm just thinking that those hoses must be fairly full of oil & for sure I can see the mess at the cooler. I figured "what's up with draining the oil" also but Rob is a fairly precise type of guy. He is very measured when he speaks about work that he's done to his Z. I figure to drain the oil & loose the filter & hope for the best. I can't afford a big mess where I'm gonna work so I got to take every precaution, besides the oil's been in mine thru the winter anyway. I'd say let me do mine first & I'll report back but I don't have the part...it's just been shipped, maybe mid week. I got other stuff on the stove too...I'm still chasing an intermittant T/O bearing noise, I think?!? I bought a phoenix bleeder & hope it's here by the weekend. I wanna re-do my coolant & do a T-stat swap out & now I figure if the oil lines are gonna be a major mess @ the rad end maybe I should just pull the shroud and do the leaf patrol also!? Seems like the perfect time & the right thing to do! Man I hate this..."while we're here, I should do...."!!!! Oh well seems like the honeymoon's over!:-({|= :sign10:

:cheers:
Tom
Oh yea, I forgot the S/S brake hoses...which I haven't bought yet!

[Aurora40]

Oh yea, I forgot the S/S brake hoses...which I haven't bought yet!
Heheh, figured I'd do that too. :)

It doesn't sound like draining the oil actually drains out the hoses very well, so I think I'll just order the hoses and swap 'em out, then top off the oil. Mine are leaking enough I'd like to get it done. I'll check out P&G. :cheers:

[Tom]

Draining the oil pan does not drain the oil cooler and lines, that's why it only takes 8.5 quarts of oil to refill a 12 quart system when you change the oil and filter normally.

Let the car sit over night before you change the lines. This will let all the oil possible drain back into the pan. Put some old newspaper on the ground under the car and rags below the fittings at the block and connection at the oil cooler to catch any oil that comes out. Disconnect the hoses at the block first and catch the oil that runs out of the lines with the rags, the newspaper on the ground will keep you from making a mess on the ground. Be prepared when you disonnect the lower hose since this is when the most oil will come out. Removing the lines at the block first will minimize the amount of oil that comes out at the oil cooler connection.

[tomtom72]

Thanks again Tom!:o I figured to let it sit overnight to have a chance and the rest just makes sense about which lines to do first. Either way I suppose the mess can't be avoided, only minimized.:mrgreen:

Bob, yea what is it with the "while we're here" thing and corvettes!?! The stuff came today from P&G so add $10 shipping from PA to NY to the prices I quoted in my other post. Oh, almost forgot don't order the O-rings, they come with the hose! Well looks like I'm gonna start my own little stash of NOS parts!:sign10:

:cheers:

[Aurora40]

d'oh! I already ordered the o-rings. A whole 10-pack as that's the only way they come...

[tomtom72]

Oh that is a rip off! P&G lets you order them individually, so like a true novice I figured that they don't come with the new lines...right?!....soooo I'm a smart guy & order two O-rings separately and when I open the box today the new O-rings are under the saftey caps on the block that bolts to the cooler!:o

One thing the new lines are made in Mex. and they are not black!

There must be a conspirecy here somewhere....sometimes with this car I feel like I'm on an episode of 24!:confused:
Everyone knows something except for me!:icon_scra

:thumbsup:
Tom

[Aurora40]

One thing the new lines are made in Mex. and they are not black!
Seriously??? Ugh, what color are they? Man, they are just trying to ugly up our engine bays...

Is it likely that the part is shared with some other application? I kind of doubt it, so why not keep the same color?

[tomtom72]

The crimps at both ends, the nuts @ the block, the metal pipes + the block hat mounts to the cooler are unpainted metal. A/C line silver and the nuts are a bronze color.

I cleaned them w/GPAR + thinner, scuffed'em and then used some epoxy modified urethane oil base gloss black with a small paint brush. Didn't take long and came out shiney but I don't know how it will survive the install! I didn't do the nuts 'cause I don't think the paint will resist scratching upon installation. I suspect that the OEM lines are steel andd the replacement is aluminium.

:thumbsup:
Tom

[Aurora40]

I cleaned them w/GPAR + thinner, scuffed'em and then used some epoxy modified urethane oil base gloss black with a small paint brush. Didn't take long and came out shiney but I don't know how it will survive the install! I didn't do the nuts 'cause I don't think the paint will resist scratching upon installation. I suspect that the OEM lines are steel andd the replacement is aluminium.
Let's see a picture!

[tomtom72]

Let's see a picture!

:sign10: You know I'm spending so much $ on ZR-1 parts that I can't seem to find the fat in the car budget to buy a digital camera.:o

But they look good installed!:D

[Aurora40]

Question, what size are the oil cooler end and the piece on the block? I can't fit an adjustable backup on the block piece because my adjustables are too wide and spread onto the cooler line connector.

So I'll go buy some open-ended wrenches tomorrow. But anyone know the size? I'm guessing the block end is a 1" and the cooler end is a bit bigger than that.

Edit: Oh, and I painted both ends. Looks much better now. I figured I can easily touch up the edges scuffed during installation.

[tomtom72]

Hey Bob, Yes the block is 1" and the line ends @ the block are 1 1/4". I don't remember if did back it up during removal...it was only last week you would think I could remember!

Any way 1" & 1 1/4" :thumbsup:

[Aurora40]

Hmm... Did you actually fit that size on it? I bought a 1" wrench but passed on the 1 1/4" and used an adjustable instead. The 1" wouldn't fit on the block part. Even after the line was off I tried it. It almost seems metric as the fit is quite close but not close enough.

I had some oil spill on the floor from the cooler. I figured it would all run out at the block, not the cooler, since the cooler is higher. So it made a bit of a mess, about a 1/4 of a quart maybe.

The new ones went on without too much trouble. After they were on, I backed the car out in the driveway and sprayed the area around the hoses down with some gentle diluted degreaser. Then sprayed that off with distilled water. Unfortunately while the car was out there and I was wiping up the floor in the garage, the sky opened up and the 'vette got rained on! :eek:

Anyway, here's the pict. The black came out great, as long as it lasts... I will touch up the edges of the block-side fittings later, but they fared pretty well as I put the wrench carefully over them:

http://members.aol.com/corvettezr11990/temp/coolerlines.jpg

Notice it's wet, but it should dry spot-free. I've had success with distilled water rinsing before without it causing spots.

[Aurora40]

Oh, Tom, are you keeping your old hose? I'm thinking of cleaning it up and maybe trying to seal/repair it. Does that seem dumb, should I just pitch it?

Also, I'm such a square I even bought a new screw for where it mounts to the cooler so it would be nice and clean...

[tomtom72]

Hey Bob, I threw my old one out...I'm sorry for the wrong wrench size on the block as I was looking at my wrench drawer & trying to figure which ones I took over to the car...sorry! The hose end is 1 1/4". Your hose looks good, I'm gonna touch up mine also. It would have looked so much better in S/S braided. I didn't think to order a new bolt, although mine is still unscratched.

Ya know mine sat for a few days with the front up on stands before I did the hose that not much came out of the cooler. I was doing some other stuff & I figured to do the oil line & samco hoses & T-stat & rad pull & clean out all at the same time. I guess procrastination pays once in a while. :mrgreen:

I should have saved my old oil line & shopped it around to see if I could have had something made at one of the heavy equipment repair places in the Bronx. :o

Your engine bay is lookin good man!! Very ship shape & 4.0!:thumbsup: