Very late to this video, because I've only recently come across AC Dodd's channel. Remarkable content and really helpful - I felt a bit guilty about relying on the QC folks at the manufacturers. I'm part way through rebuilding a 1098 engine at the moment - a process that has become far more thorough thanks to your videos! Thanks for your help.
I'm on the edge of buying an SPI and having my first mini since a 1275GT 35 years years ago (oh to still have that..). I've found your name and info many times in the forums, and hence the reason I ended up here. I'll be binging your videos over the next while. Something that had blown me away was a pic someone put up on your cams and the power gains. Tbh, I've no idea where to start with an SPI. I could and did play with an original mini 74.7 pistons, 1473cc, 8 port head etc etc. 4 lifetimes ago though. Watching you just makes me realise how much I never knew. Gonna have fun watching this stuff. Thanks for sharing
@@ACDoddI agree fully. A friend has an abandoned project which may be coming to me for a very agreeable mate rate though. Gift horse, mouth, etc etc..
Great video. Just fitted an oil pump - typical. Did take it apart to clean and measure it. The tolerances were good (lobe and annulus) but did not know to alter the tolerance on the back (not that I've got a lathe. Wish I'd bought one from you now!
This might be a dumb question, but how is the rotor attached to the rotor shaft? It looks like just a press fit. If that's the case, wouldn't it just slip with the oil resistance? Also, there's a small dot punched in the rotor, what's the purporse of that? thanks.
No chance of slipping with the correct interference fits. You can shear the drive off the end of the shaft before the shaft will spin the rotor if the interference fit is correct.
No need for a lathe on such a small aluminum part, wet or dry 200 or so is good, that VERY COARSE paper you used on the steel left a horrible finish and would have just about destroyed the aluminum to steel seal with the end plate if used on it. Like you said 'ground finish' on the end plate and should be the same for the rest of the steel parts that are going to contact it and especially contacting the aluminum housing. Also, DO NOT pack with grease, a light smear, enough to take up the clearance is all they need. Otherwise nice video, thanks.
No as they won’t accept that, as it wilL meet the spec of the OE part. What I am assembling here is much better tighter unit. It not uncommon if you buy 20 pumps that 1 or 2 are not good enough for this.
Interesting. Thank for the vids. What grit do you use for lapping? Also could one lap the casing down to size instead of a lathe? Endplay in mm is 0.00762mm right? pretty close to zero!
@@ACDodd Lastly. 80 grit is fairly rough. Is this for kepping an oli film in place thus lubing the moving parts and keeping up pressure? Also, do you mix and match parts from diffent pumps to make the optimum fit/size/cleance? Again, thanks for you time.
@@no66 80 grit is so the paper does not clog. Yes you can mix and match if you buy enough of them but it’s usually not neccesary and you will not have as many useable pumps after the process as when you started
Sorry but the imperial meassurement makes me crazy. 5 thousands in metric you can't meassure with this tools... What kind of abrasive you're used for "lapping"? It looks horrible...
Very late to this video, because I've only recently come across AC Dodd's channel.
Remarkable content and really helpful - I felt a bit guilty about relying on the QC folks at the manufacturers.
I'm part way through rebuilding a 1098 engine at the moment - a process that has become far more thorough thanks to your videos!
Thanks for your help.
Loved this video. Thanks. Real school day stuff.
Thankyou
I'm on the edge of buying an SPI and having my first mini since a 1275GT 35 years years ago (oh to still have that..).
I've found your name and info many times in the forums, and hence the reason I ended up here.
I'll be binging your videos over the next while.
Something that had blown me away was a pic someone put up on your cams and the power gains.
Tbh, I've no idea where to start with an SPI. I could and did play with an original mini 74.7 pistons, 1473cc, 8 port head etc etc. 4 lifetimes ago though.
Watching you just makes me realise how much I never knew.
Gonna have fun watching this stuff. Thanks for sharing
@@GPZ_Bikerif you want a mini to modify I would suggest you focus on a carburettor model, much larger scope for more power.😊
@@ACDoddI agree fully. A friend has an abandoned project which may be coming to me for a very agreeable mate rate though. Gift horse, mouth, etc etc..
Very informative next time I need a rebuild I will get 1 of your pumps
Just bought one 👍👍received today
Cool, thankyou!
Great video. Just fitted an oil pump - typical. Did take it apart to clean and measure it. The tolerances were good (lobe and annulus) but did not know to alter the tolerance on the back (not that I've got a lathe. Wish I'd bought one from you now!
The RX-8 has one of these Pumps, and i thought about how it works. Great Video!
Nice learnfull video's AC 👍Keep on uploading this kind of video's, I will be watching them 😀
great video just shows how much they are out and a AC Dodd pump with good tolerances
Great vid AC👍 I honestly didn’t understand why and how, now I get it !
Love your videos AC!
I love them videos thanks for taking the time to show us.
AC did you ever fitted an oil filter (“Oberg Filters) before the oil pump?
Best instructive Videos!
No, but it is beneficial
10 thou on a brand new pump! QC man was out that day!
You are responsible for checking every component that goes into your engine.
Great video, do these tolerances apply to any pump of this design or just the A series one?
Clearly these tolerances apply to this type of pump, each application needs to be assessed on what is possible with each application and design.
This might be a dumb question, but how is the rotor attached to the rotor shaft? It looks like just a press fit. If that's the case, wouldn't it just slip with the oil resistance? Also, there's a small dot punched in the rotor, what's the purporse of that? thanks.
No chance of slipping with the correct interference fits. You can shear the drive off the end of the shaft before the shaft will spin the rotor if the interference fit is correct.
Same tolerances for 998 pumps?
Yes
No need for a lathe on such a small aluminum part, wet or dry 200 or so is good, that VERY COARSE paper you used on the steel left a horrible finish and would have just about destroyed the aluminum to steel seal with the end plate if used on it. Like you said 'ground finish' on the end plate and should be the same for the rest of the steel parts that are going to contact it and especially contacting the aluminum housing. Also, DO NOT pack with grease, a light smear, enough to take up the clearance is all they need. Otherwise nice video, thanks.
That’s your view, and not what I actually find in practice.
👍😍
So what happens if any part is out of tolerance? Return it?
No as they won’t accept that, as it wilL meet the spec of the OE part. What I am assembling here is much better tighter unit. It not uncommon if you buy 20 pumps that 1 or 2 are not good enough for this.
@@ACDodd bummer.
Interesting. Thank for the vids.
What grit do you use for lapping? Also could one lap the casing down to size instead of a lathe?
Endplay in mm is 0.00762mm right? pretty close to zero!
Too many zeros! 0.076mm. Yes I used to lap them before using the lathe, p80 is ideal. You must keep it parallel with the bottom of the recess.
@@ACDodd Ah, of couse, 0,076.
Glass plate under for lapping?
@@no66 just a flat surface is ideal.
@@ACDodd Lastly.
80 grit is fairly rough. Is this for kepping an oli film in place thus lubing the moving parts and keeping up pressure?
Also, do you mix and match parts from diffent pumps to make the optimum fit/size/cleance?
Again, thanks for you time.
@@no66 80 grit is so the paper does not clog. Yes you can mix and match if you buy enough of them but it’s usually not neccesary and you will not have as many useable pumps after the process as when you started
Could have saved her the pain and used a green rizla paper 😅
Sorry but the imperial meassurement makes me crazy. 5 thousands in metric you can't meassure with this tools...
What kind of abrasive you're used for "lapping"? It looks horrible...
Use P80 grit abrasive paper. Simply convert to metric 0.005” x 25.4 = 0.127mm