Hello all,
The rebuild of my 1951 Rapide continues at its snail pace. Having finally installed the main bearings after some fettling, I am now struggling with the oil pump. The old one was quite badly worn on the worm drive so I am fitting all new parts. Richardson says the pump sleeve should be a slide fit, however I have read elsewhere sometimes it needs the casing heating to get the old one out. This was my experience. I was hopeful that the new one would be a slide fit, but no such luck. After four attempts, leaving the sleeve overnight in the freezer and heating the case has allowed me to install it; it still needed driving in, which is a long way from a slide fit. Now, of course, the pump rotor won't go in. It tightens up where the slim end of the rotor enters the housing at the far end. The book says it may have to be replaced by different parts to ensure the correct fit, as the parts are paired.
Firstly, should it be so hard to get in? Other users experience welcome.
Second, what now? Once the case has contracted after heating, the sleeve is obviously now too tight. Presumably it will have to come out again. When it's out, am I likely to be able to select a better fit, or should I think about having about a thou taken off the OD? Or ream the housing or the sleeve in situ?
The rebuild of my 1951 Rapide continues at its snail pace. Having finally installed the main bearings after some fettling, I am now struggling with the oil pump. The old one was quite badly worn on the worm drive so I am fitting all new parts. Richardson says the pump sleeve should be a slide fit, however I have read elsewhere sometimes it needs the casing heating to get the old one out. This was my experience. I was hopeful that the new one would be a slide fit, but no such luck. After four attempts, leaving the sleeve overnight in the freezer and heating the case has allowed me to install it; it still needed driving in, which is a long way from a slide fit. Now, of course, the pump rotor won't go in. It tightens up where the slim end of the rotor enters the housing at the far end. The book says it may have to be replaced by different parts to ensure the correct fit, as the parts are paired.
Firstly, should it be so hard to get in? Other users experience welcome.
Second, what now? Once the case has contracted after heating, the sleeve is obviously now too tight. Presumably it will have to come out again. When it's out, am I likely to be able to select a better fit, or should I think about having about a thou taken off the OD? Or ream the housing or the sleeve in situ?