Replacing oil line (engine to thermostat)

Decolliber · 05-24-2003, 03:12 PM

I have noticed a very slight leak in the oil line from the thermostat to the engine (930 101 743 12, p. 13 in parts & tech reference catalogue). The leak is at the point where the rubber section at the rear is crimped on to the metal part of the pipe. Two questions:
1. Is this leak likely to just gradually get worse, or could it suddenly get much worse (eg, by the rubber separating from the metal crimp)? Right now the leak is just a tiny amount of seepage, not even enough to leave an oil drop on the ground.
2. When I do change the pipe, will I need to wait until an oil change, or can I just jack up the car on the right side?

North Coast Cab · North Coast Cab's Garage

It will most likely slowly get worse. You need to do the change when the oil is drained. Also, do a search as removing these lines from the t-stat can cause major t-stat thread heartache. Since it's an '88 you should be ok. Wayne sells the lines for $65-70 and it may be worth while changing them both while you're down there. If the threads are ok on the t-stat you can do the whole job in 15 minutes.

JG

Decolliber · 05-24-2003, 03:47 PM

I was just browsing through Pelican parts list for these lines and noticed a warning about the thermostat threads, and a device described thus:

If you have recently removed the oil lines from your thermostat, you may have found that the threads that attach the oil line to your thermostat have been removed with the oil line! Don't despair, our 'thermostat saver' is a small cap that that you can reattach to the thermostat and then attach the oil lines. No need to purchase a new thermostat because the steel lines have gummed up the soft aluminum threads. Simply install the thermostat saver with a bit of locktite, and you should now be able to attach and remove oil lines without any fears.

Thermostat Saver, 911/911 Turbo (1974-89) [Photo]
PEL-PP901687

Should I also buy the set of four oil line wrenches (27, 30, 32, 36 mm)? Why not just use two adjustable wrenches?

TurboRuf · 05-24-2003, 05:36 PM

I had to replace my two oil lines to the thermostat a while back on my 930. I had the same problem with them leaking at the crimp points. I had no problems with my thermostat threads, so remove your lines first before buying the Thermostat Saver.

As for the oil line wrenches, I would highly recommend them. The lines are on very tight and you could easily strip the large nut using an adjustable.

Tim Polzin · 05-24-2003, 07:09 PM

John:

i just replaced that very line last week. My leak was identical to yours. The 36 mm nut on the tstat was the more difficult to get off, but it did come off with no damage to the Tstat.

Probably better to drain the oil, but I did it with just raising the right side as high as my jack stands could take it, then left it sit for a couple of hours. I only lost about 10 ml of oil.

Let me know what you pay for the line. Mine was considerably more than $70. The other line from the Tstat to the tank was fine.

Tim

Decolliber · 05-25-2003, 06:37 AM

Doing a search, I discovered a lot of threads on this subject, including the suggestion to soak the connections in PB Blaster for a few days. Chris Bennet and a few others recommend cutting the nut at the thermostat end of the line. I gather that the technique is to cut the nut on opposite sides with a dremel, and then pry it off with a chisel, to avoid stripping the aluminim threads on the thermostat connection.
Have to buy one of those dremels. They seem to come up often on this BB, as an all purpose tool. Any recommendations on one that has all the necessary attachments? Sears has one with a lot of attachments for about $70. harbor Freight has much cheaper ones.
Tim Polzin: Pelican charges $69.75 for the oil line from the engine pressure pipe to the thermostat (that other place, V****x charges $90). But The Other Place only charges $55 for the oil line wrenches, Pelican charges $65.

KTL · 05-25-2003, 10:34 AM

I also recommend the set of wrenches. They're pretty handy if you do alot of wrenching on your 911 and your friends 911's as well. I have used these much more than I thought I would.

The oil line is definitely going to leak more with time. That's a pretty critical line with a lot of oil running through it. Hate to see that one develop a large leak!

The Dremel/rotary tool is a handy thing to have without a doubt. Sears will occasionally have a sale on their Craftsman rotary tool. Keep an eye out for the sale coinciding with Craftsman Club Days and you can use your Craftsman Club discount for an extra 10%.