| Author | Message | ||
     Roderick Waite Frequent User Username: rodwaite Post Number: 89 Registered: 1-2012 |
On start-up of my 1984 Silver Spirit, there is a loud whirring noise that relates directly to engine revs.It seems to emanate from a belt driven unit on the right hand side of the engine, tucked inside the loop of the top radiator hose. It has a black plastic lid, on which it says to fill to the mark, do not overfill, and use approved fluid. There's no fluid in there, the short black dipstick remaining dry. What is this unit, please? It seems steering related insofar as you can feel slight vibration through the steering wheel. And what is the 'approved fluid'? Help! And thanks in advance! Rod '84 Spirit | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 552 Registered: 6-2009 |
Rod, What you describe sounds like the power steering reservoir. It's pictured here at the upper left for the pump itself and lower right for the seals:  According to Chapter D of the workshop manual Dexron II automatic transmission fluid was what was originally used for the power steering system. At this point in time you'd have to get some manufacturer's Dexron-III equivalent (GM no longer formally licenses to the Dexron-III spec), and that's fully backward compatible with Dexron-II. However, if your reservoir is empty you've sprung a major, major leak somewhere. Check all your hoses and the steering rack. If you refill I'm sure you'll find the location of your leak in very short order. I hope this hasn't been in the empty state for long or else a steering rack rebuild is almost certainly in your near future. Brian | ||
| Mark Aldridge Prolific User Username: mark_aldridge Post Number: 105 Registered: 10-2008 |
Rod, check underneath that the steering rack bellows are not bulging with fluid indicating a rack seal failure. If this is the case, you will shortly have a "lake" of Dexron under the car. Do not run the car with the steering fluid level low, you will ruin the pump. Mark | ||
| Roderick Waite Frequent User Username: rodwaite Post Number: 90 Registered: 1-2012 |
Hello Brian, and Golly! - that was quick! That is indeed the unit at fault, and indeed the reservoir is empty. But where does/did the oil go? There's no drips on the garage floor - I recently had the engine cleaned when I replaced all the LP hydraulic hoses on that side of the engine, and there's no oil to be seen anywhere. I have never checked that level before, so don't know if it ever was full. Unless it's emptied itself somewhere else, of course, which is entirely possible - she does quite a lot of mileage. Living in rural France means my options for special oils are limited. I don't know what fluid was in there to start with. Would a standard transmission fluid be adequate? The usual supplier here is Total, of course, which isn't even mentioned in The Book. Incidentally, my copy of the manual is woefully inadequate - Chapter D has 4 pages and no pictures whatsoever. It would seem that my first job is to re-fill the reservoir with ATF and see what happens on start-up. I'll try that tomorrow ... I may be back ... watch this space! Many thanks ... stay well Rod '84 Spirit | ||
| richard george yeaman Prolific User Username: richyrich Post Number: 103 Registered: 4-2012 |
Rod, it could also be a hole in one of the pipes going to or from the rack or pump, Richard. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 553 Registered: 6-2009 |
Rod, One very important data point that was missing was, "she does quite a bit of mileage." That being the case, you could very well have a slow leak, of which you were clearly unaware, and the car has been doing a slow drip, drip, drip while being driven for heaven knows how long. However, being without any fluid should have effectively shut down your power assist and been immediately noticeable. You've received several good additional pieces of advice since my first post. The fluid that would have been in there to start with is almost certainly automatic transmission fluid (ATF) that was either Dexron-II spec if still the original fluid or Dexron-III spec if refilled later. Since GM automatic transmissions are so common worldwide due to their generally "bulletproof" nature that even our cars use them, finding ATF that is Dexron-III spec is about as simple as you can get. I don't know of an auto parts store virtually anywhere that doesn't have some maker's ATF that meets the Dexron-III spec on their shelf. A great many of these are Dex/Merc formulations that comply with Dexron and Mercron specs. Brian | ||
| Roderick Waite Frequent User Username: rodwaite Post Number: 91 Registered: 1-2012 |
Hello Mark, and thank you for the info:! I had a grovel under Echo, and found the steering rack bellows appear normal, ie: no bulging. I was very unhappy about running the engine too, so I rang my mechanic friend and he concurs - so he'll come over here tomorrow morning to get started on tracking the problem down. What a great forum this is, a source of comfort to all us amateur owners! Stay well Rod '84 Spirit | ||
| Roderick Waite Frequent User Username: rodwaite Post Number: 92 Registered: 1-2012 |
Hello Richard, and thank you - as Brian just said, it could well be a slow leak over a long period, and a pin-hole would do it. Hopefully I'll find out in the morning! As to the steering itself, as I said there is a slight feel of vibration through the wheel when a little lock is applied. Coming out of my garage requires an immediate full right lock turn, which so far has been accomplished with no perceptible change in steering behaviour. But I have no intention of pushing my luck any further! Echo stays in her garage until this is sorted out! Stay well Rod '84 Spirit | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1089 Registered: 6-2006 |
Rod , remember that when you get to lock and it starts making the whirring / growling noise - you should let the wheel off about 4cm until the noise ceases. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 555 Registered: 6-2009 |
Given what I've read about the SY/SZ steering racks I really try to avoid going to full lock if at all possible. I get close at times but, as Paul notes, the moment I hear what I call the "full lock noise" I back off just the slightest bit and it stops. I'll add this isn't distinctive to RR/Bentley cars, either. Our Buick and GMC truck both have "full lock noises." However, since this is a power steering thread, and the opportunity is presenting itself to discuss filters, I shall. Is installing one of these as simple as splicing the return line from the rack to the pump and putting one in there? What precise type of filters have people been using in this application? From photos they often look like inline fuel filters, but I'm doubting that's what they actually are. If your pump reservoir isn't empty I presume that one must pinch the line shut just upstream of where one intends to cut to prevent Lake Dexron from forming. Brian | ||
| David Gore Moderator Username: david_gore Post Number: 1318 Registered: 4-2003 |
I suspect the noises are caused by air entrapment in the circulating fluid due to its low level in the reservoir. There is apparently enough fluid left for the power assistance to be maintained however the level of steering input required will noticeably increase once the fluid level is too low to avoid significant air entrapment. I would drain and replace the fluid as a matter of priority. Once the reservoir is full, raise both front wheels off the ground, start the engine and turn the wheels from lock to lock several times, check the fluid level and top-up if necessary before repeating the lock to lock procedure. Continue this procedure until no further topping-up is required. | ||
| Roderick Waite Frequent User Username: rodwaite Post Number: 93 Registered: 1-2012 |
Good morning everyone, and Frank (my mechanic friend) duly arrived, complete with a tin of Total ATX (their equivalent of Dexron 3), had a look in the reservoir to find the level down just below the curve of the swash-plate housing, and clean. In went the ATX - engine start. Blessed silence! Under Echo, and sure enough there's a slow drip from one of the new hoses! The new rubber had compressed enough to let a seepage through - so the whole lot got tightened again, all 6 hoses both ends. Ticked over for 20 minutes, no new drips. Lock to lock with ease - I do get the the 'full lock groan' so ease back a bit when I hear it - glad others have experienced this! I will be watching this for a while, but the problem seems to be solved without consequent damage, for which I am truly thankful! My thanks to all who have assisted me with cogent advice, as I have come to expect from this forum! Not all are as helpfully forthcoming, you know! Stay well Rod '84 Spirit |
