[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
On 25 Dec 2004 at 8:37, rjdiaz wrote: > Questions: > > a. Should I use a thinner oil? Castrol is easy to get at > the base but not in a wide range. The price of oil out in > town is prohibitive. Especially in the winter, I believe this is a very bad idea. Thicker oil seems attractive because we tend to think that it will lead to higher oil pressure. It certainly does, but mainly within the oil passages. The main oil pressure, however, is generated hydrodynamically within the bearings and journals themselves and does NOT show up on your pressure gauge. Heavier oil in cold weather will actually be counterproductive since it increases the time after startup during which oil does not actually get to the bearings. Heavier oil also puts more strain on the oil pump, because it takes more HP to force that thicker stuff thru the passages. This not only wastes HP, but also causes excess wear on the pump parts. I'd stick with something like 10W-30 or 15W-40 depending on the temperature. > b. I'd like to get a re-build kit for the fuel pump in case > it's leaking but I'm having trouble finding it. Does anyone > know who sells quality kits? There were probably different pumps used in type 3s over the years, so I THINK you will have to describe yours first. Be aware that you can probably use a type 1 kit if you reuse the type 3 springs. The springs are different because the springs determine the output pressure, which is slightly different for type 1s and type 3s. I'm not convinced that the difference is significant, but if it were my car, I'd make every effort to make sure it had the right springs in it.. > c. Any thoughts from the group on the high lead in the oil analysis? > What is the make up of the bearings on these original engines? Don't know, but in the US even the lead substitutes don't contain lead. I would not trust any analysis that did not come from a car in regular use, since acids that accumulate in the crankcase may leach material from the bearings chemically. I would also not trust an analysis from runs using inappropriate weights of oil, which in my opinion you've been using. Frankly, I'm not even sure that the VW bearings contain lead, but I suspect that that they do. There's also the possiblity that the oil analysis is slanted toward the vast majority of engines that actually have oil filters. The analysis company would have to tell you whether this would make a difference. I think it's quite possible that in this day and age they haven't even considered this possibility. Finally, you may need to recognize that the leaded gas of the past left residue in the crankcase and oil passages that would stay there virtually forever. (Remember the grey "goo" that used to always cover the oil sump plate when you changed the oil in the old days? Much of that was lead.) Well, if this is an old original engine that has seen little mileage in the past 20 years, then there is probably a lot of that residue still in there. I don't know if the oil analysis can differentiate this residue from bearing lead, but it might be a reasonable question to ask the analysis people. I guess that overall, I'd want better evidence that this engine actually needed a rebuild. Yes, switch to lighter oil, get a compression tester, and wait for warm weather and give this baby some nice warm highway miles and a few oil changes. Then maybe you will have a better idea of whether you actually have a problem or not. BTW, the most likely things to give you a problem are the exhaust valves. You can check the valve to valve guide slop while adjusting the valves. This is probably the thing you should be watching and thinking about. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~