Welcome to our resource for MG Car Information.
MG TD TF 1500 - Steering Rack Lubricant - again
I am about to add the lubricant to the steering rack. Checked the archives. What is the latest thinking about using (heavy) oil or grease? |
Bill Thienes |
Bill - Gear lube is what the book calls for and is what I use. My thinking is that there are ball joints at each end of the rack, where the tie rods attach, and the lube oil will flow into the joints metter than grease will. The down side of using oil is that it will leak out of any place that is not sealed properly (and you can't tell where these places are until you put the oil in). It is also hard to get into the rack housing (see the following article on making a high pressure oil gun: http://www.omgtr.ca/technical/highpressureoiler/highpressureoiler.htm I know of a lot of people who advocate the use of grease instead of oil. The advantage is that it is easier to get into the assembly and is not such a mess if a leak develops. The down side might be that it would not work it's way into the ball joints as well as oil does. In spite of my preferance of oil, the people who are using grease do not appear to have had any problems that I am aware of (on of our local register members has used it in his cars for years and he drives the cars enough that if there was going to be a problem, it should have shown up by now). Grease in nothing more than oil suspended in a thickening agent, so... Finally, more important than which lubricant is used, it is more important that some kind of lubricant be used. Now you are still faced with what to use and have just spent a few minutes being confused by my nattering on the subject - bet you are sorry you asked ;) Cheers - Dave |
David DuBois |
Bill, I used Dave's oiler gun design on the TF and it worked perfectly (gear lube). Greg |
Greg Van Hook |
I shot a heap of hypoid (200ml?) into the zerk, made the steering feel a lot lighter. PO had used grease; the oil revealed the left boot leaked. |
Will |
Oil and grease have two different types of applications. Lubrication with oil consists in forming an oil film between the two surfaces. Doing so requires that the two surfaces are animated by a constant movment at a minimum speed. For reciprocating movments or low speeds the oil film cannot be formed, and grease is required. It is an evidence that the rack falls into the second case. When lubricating the rack with oil, the contact metal to metal will occur, this is why an EP oil, which contains contact friction modifier, is recommanded. This is to explain that grease can properly do the job, anyway, for practical reasons, I vote (and use) grease. |
Jean-Marc Thély |
I've allways thought the best way to destroy a steering rack is to use grease rather than oil. If you pump grease in via the central nipple (zerk) it will travel along the rack tube and lubricate the gear but you will have to virtually fill the boots to lubricate the ball joints. If you do this when on full lock one of the boots will be closed up and the only place for the grease to go is back along the rack tube to the other boot. The grease being thick won't flow that well and you run the risk of the closed boot exploding. The other problem is the top pinion bearing - actually the rack housing casting. When I bought my car the rack was filled with grease and the pinion shaft and housing were badly worn. They were so dry that they were pitted with rust. Fortunately I was able to do a repair using an oil seal sleeve over the shaft - it's now filled with oil ! Jan T |
Jan Targosz |
What would be recommended if both have been used? I use oil, but it appears the PO used grease. Any good suggestions for cleaning out the unit? |
Bruce Cunha |
Lindsay Porter's Complete Service Guide for the MGB shows a useful way to fill the steering rack gaiters with oil. Jack up one front wheel at a time, loosen off the outer clamp, slip a thin oil can nozzle into the gaitor and pump in the required amount. It worked well for me although I must admit I now use a small Draper grease gun filled with oil to pump oil into the grease nipple of theTF. John |
John James |
I think I have found a good compromise by using semi-fluid grease, the type used for pre-war motorcycle gearboxes which did not have oil seals. I take the Penrite product and add 10 % molybdene disulphide (Molykote) to get EP properties. This lube can be pushed from side to side without danger of the bellows exploding and it flows into the inner ball joints. I have some leakage from the top pinion bearing (so this won't rust!). Contrary to the book I re-lube the rack every time I do the rest of the suspension, but give it just one push of the gun, for a slow, steady renewal of the lube. After 5 year ith quite a lot of use no perceptible wear has occurred at the rack or joints. |
Remo Peter |
When these cars were new, I think most greases were really very primative, caked up, and were not really good. Obviously grease from the center nipple cannot get into the outer ball joints, hence the recommended oil. I personally feel modern grease works quite well. Of course the outer joints must be lubed when changing the rack seals. If the bellows are checked and maintained, the joints will stay well lubed for years. I seem to never get over 5 years or so for the bellows, and things are always quite well lubed. |
George Butz |
When rebuilding my rack assy, I found .007 wear on the right end of the rack (LHD TD). The former owner used grease, which was a bear to clean out. See recent thread on steering slack. I now use oil. Jan |
Janson Hurd |
To follow up on Bruce Cunha's question and at the risk of offending purists, what would be the harm switching from previously using grease to now using oil without overhauling the steering rack? To the extent that grease is soluble in anything, it is soluble in oil (in other words, the grease won't congeal if oil is added, rather it will be made more mobile). Why wouldn't this provide the best of both worlds--the better "stickiness" of grease to some of the rack surfaces and the fluidity of oil to reach the far ends of the rack. I now run for cover before I wind up with the separate advocates of grease and oil each shooting petrochemical products my way! Larry |
Larry Shoer |
Years ago I assembled an MGA, including a new rack, which I lubed with oil per book. I drove this car frequently, with its owner as passenger. He liked for me to go FAST. He had it lubed at the local gas station, then had me drive him to work, over the twistiest road available. The first switchback at speed, I threw it in the first part of the turn, and the damn steering did not return as I was used to, with a most frenzied attempt to get it back. The *** had filled the rack with grease, which does not flow from end to end on a tight rack on a cool fall morning. I do not EVER want to experience this again! He ordered me to clean, flush and refill with oil. I removed the boots, scraped out as much as possible, put some kerosene in, drove it. Drained and filled with oil. When assembling a rack, I put half the oil in each boot before closing. FRM http ://www.usachoice.net/gofanu |
FR Millmore |
"what would be the harm switching from previously using grease to now using oil without overhauling the steering rack? To the extent that grease is soluble in anything, it is soluble in oil (in other words, the grease won't congeal if oil is added, rather it will be made more mobile)." That was precisely my theory too, when I just filled the rack with hypoid oil. It sloshes around with what grease is already in there. The liquid that eventually came out (hole in gaiter) is black like moly grease and much thicker than the oil that went in. All the blobs left on the floor... they have not separated out but have stayed mixed. For all intents & purposes, I think its 100% safe & satisfactory to do it. |
Will |
Molykote, 'Longterm 00' is a semi-fluid grease which contains Moly. Besides O.E.M. industrial gearbox applications, it is used in leaky old gearboxes inplace of ISO 100,(SAE 75W-90) or ISO 150 gear oil (SAE 90). Go to www.molykote.com to find a distributor in your area. |
S.R. Barrow |
I am now restoring my mgtc bishop steeringbox. My mg has never been restored before and it is from 1949. None of the parts are worn exept the lower ball bearing. The tube was full of grease allmost to the steering wheel. The solution of our problem is I think to untighten the 4 bolds of the endplate before greasing so that the grease can come out there. Then tigten the bolds and grease again. I am sure that oil will leak out via the sector shaft. R.Mantel Netherlands |
R.Mantel |
This thread was discussed between 15/06/2004 and 03/07/2004
MG TD TF 1500 index
This thread is from the archive. The Live MG TD TF 1500 BBS is active now.