So, you think you can refurbish your own oil pump?
Posted: Mon Jul 02, 2018 11:42 pm
Well, of course you might be able to... But I totally know now that I shouldn’t...
A few (cough!) years back I rebuilt the oil pump for my F1 with some seals I got from the ill fated TwoStrokeShop. They didn’t come with a gasket as Steve couldn’t source that but it was a half decent kit and all I needed was a special ‘screwdriver’ for the 3.5(IIRC)mm special bolt and I was away.
I found some online info and TSS did some kind of guide, armed with those and the special screwdriver’s arrival from China, I got on with it. I can’t remember exactly how careful I was in what I did but as you know I’m no stranger to taking things apart and putting them back together. I didn’t consider what I did to be slapdash and as this was my first ‘inside the pump’ foray I felt that I took my time to get it right. I even remembered to clean out the NRVs and did some work in setting it up after. When fitted I ran the engine up a little bit, but as it is (still) not painted I didn’t ride it.
Now then, since I did that work a bloke called Arrow on the forums had begun to offer a service to refurbish oil pumps for Yamaha models. He does a bunch of the Yamaha pumps including the TZR/TDR and RD/RZ models and as anyone who’s had him work on their pump knows, he really knows his stuff. I was very lucky to be able to visit him last month and had a great afternoon talking pumps. I know we would get on from our email conversations over the years, and I’m pleased to say that I wasn’t wrong, he’s a totally good bloke who really knows our pumps and does wonderful work. He showed me round his workspace, his special tools and even his spares stash. He filled me in on how they work, how they can be adjusted also educated me some of the wear issues with these units and how they differ over the years and from other models. Refurbishing these pumps actually requires a lot of work, far more than you might expect. The main thing I worked out very quickly, Arrow is an Expert, with a capital E. Nuff said.
Ever since I knew I’d be in the UK I had arranged to have Arrow look over the pump I’d rebuilt and see how just how well I had done. I felt that my work might be indicative of what any of us might achieve at home and that Mr Pump would be able to give me his honest opinion about my efforts. You might think it’d feel a little daunting to expose myself in this way, but as you know I don’t mind admitting my mistakes in public and felt it might be educational, for you guys as well as myself. This is what he said in his message to me on taking it apart:
Hi Jon, I opened up the pump that you built.
On the plus side;
- All screws nice and tight.
- Seals fitted correctly.
- Nozzles fully home, no gaps underneath them.
On the negative side;
- Gear fitted wrong way round, this puts a bit more strain on it due to the drive.
- Front plain thrust washer wrong way round, best to keep parts that have run together, together, witness marks etc.
- Both check valves passing heavily. Very fussy item that needs scrubbed seats and close inspection. Pump must be spotless through out to prevent re-contamination.
- No rework on shafts.
- No grease in front housing.
Eek... Well I knew he was being kind when he started off with a positive about the screws being tight LOL Obviously there are some serious issues here, backwards gears, passing valves and the lack of grease that should have been obvious really and luckily none of the silicone I used to stick the gasket back together had got in the pump that would have been catastrophic if id been heavy handed there of course and I know that worried him when I told him what I had to do with the gasket.
The good news is that the pump has now been fully refurbished by Arrow and as we’ve come to expect it looks amazing, better than an new OEM unit. Spending time to learn about the process means that I now know that beauty is much more than skin deep with Arrow’s work though and I can be confident about using this pump on my bike now, unlike I was (and rightly so) before.
As an aside I also had him work on a 250 pump I had. I picked it at random from a box of them that I had lying about as I’ve never rebuilt a 250 before so they just sit in their own filth in a box, poor things. When I collected it after the refurb I was shown that this very pump was a great example of just how worn some parts of these pumps can get. Here are two parts that should not have any wear... Just look at the steps!
When we measured the screw shaft wear Arrow quickly worked out that the pump was actually providing a negative stroke! Scary and probably what killed that engine perhaps leading to why it ended up in my spares. There was even wear on the pulley from where the throttle had been pinned so many times, taking these wear elements together it was deduced that it was probably off a bike that had been raced. What was especially interesting was that the bore was perfect and internally it was in great condition, yet more testament that these pumps were designed and built well; 35 years of abuse and it was still working on a machine that the manufacture never expected to have anything like that many birthdays.
Looking back at what I’ve written I see that I haven’t included many photos here... It’s a crazy fact that there seems little point putting up yet another photo of an Arrow perfectly restored pump, literally hundreds of them have already been posted by happy customers and we’ve all seen them before on the forums and my own restorations include them too. We all know they look glorious, and are just like 'yeah yeah' lol. Ok... Perhaps this pic of 3 in a group might be a little different LOL
So what have I learnt? Well... Pretty much I confirmed what I already knew that this work is best left to the professionals, especially now that we have a tame one in our midst. It cemented my view that that you cannot hope to replicate the work done by a Pro on a part so integral to the longevity of our expensive engines. Just a few minutes after meeting him, Arrow showed me his ability to look at parts and identify them as wrong for the pump in question and/or see what’s wrong with them even without measuring, he’s done that many of them now he just can tell at a glance. Spending time with him proved to me that we are very lucky to have him; his knowledge with these units is invaluable and that he has a waiting list for his services for a reason.
Often I see posts on the forums from people who want to do their own pump refurb and I (and others) always post to advise them to send it to Arrow. Sometimes they moan about the price, especially of shipping if living outside of the UK, but really this is a key component of our engines and the cost of a pro working on it is actually just cheap insurance, especially after all the big money some of us spend on cylinders and cranks. As the man himself told me, ‘The work I do on these pumps means they wont just work for another year or two, they will be good for another 30+ years’. After actually seeing what he does from start to finish, most of which you don’t see (refinishing, grease etc) or he doesn’t brag that he’s done (small mods for longevity, swapping parts for better ones in his spares and detail refinishing of edges and lapping surfaces etc), I’m not surprised by that. In conclusion, I think we are very lucky to have him, I know that I don’t want to go back to making a mess of my own pumps, I doubt you do either.
A few (cough!) years back I rebuilt the oil pump for my F1 with some seals I got from the ill fated TwoStrokeShop. They didn’t come with a gasket as Steve couldn’t source that but it was a half decent kit and all I needed was a special ‘screwdriver’ for the 3.5(IIRC)mm special bolt and I was away.
I found some online info and TSS did some kind of guide, armed with those and the special screwdriver’s arrival from China, I got on with it. I can’t remember exactly how careful I was in what I did but as you know I’m no stranger to taking things apart and putting them back together. I didn’t consider what I did to be slapdash and as this was my first ‘inside the pump’ foray I felt that I took my time to get it right. I even remembered to clean out the NRVs and did some work in setting it up after. When fitted I ran the engine up a little bit, but as it is (still) not painted I didn’t ride it.
Now then, since I did that work a bloke called Arrow on the forums had begun to offer a service to refurbish oil pumps for Yamaha models. He does a bunch of the Yamaha pumps including the TZR/TDR and RD/RZ models and as anyone who’s had him work on their pump knows, he really knows his stuff. I was very lucky to be able to visit him last month and had a great afternoon talking pumps. I know we would get on from our email conversations over the years, and I’m pleased to say that I wasn’t wrong, he’s a totally good bloke who really knows our pumps and does wonderful work. He showed me round his workspace, his special tools and even his spares stash. He filled me in on how they work, how they can be adjusted also educated me some of the wear issues with these units and how they differ over the years and from other models. Refurbishing these pumps actually requires a lot of work, far more than you might expect. The main thing I worked out very quickly, Arrow is an Expert, with a capital E. Nuff said.
Ever since I knew I’d be in the UK I had arranged to have Arrow look over the pump I’d rebuilt and see how just how well I had done. I felt that my work might be indicative of what any of us might achieve at home and that Mr Pump would be able to give me his honest opinion about my efforts. You might think it’d feel a little daunting to expose myself in this way, but as you know I don’t mind admitting my mistakes in public and felt it might be educational, for you guys as well as myself. This is what he said in his message to me on taking it apart:
Hi Jon, I opened up the pump that you built.
On the plus side;
- All screws nice and tight.
- Seals fitted correctly.
- Nozzles fully home, no gaps underneath them.
On the negative side;
- Gear fitted wrong way round, this puts a bit more strain on it due to the drive.
- Front plain thrust washer wrong way round, best to keep parts that have run together, together, witness marks etc.
- Both check valves passing heavily. Very fussy item that needs scrubbed seats and close inspection. Pump must be spotless through out to prevent re-contamination.
- No rework on shafts.
- No grease in front housing.
Eek... Well I knew he was being kind when he started off with a positive about the screws being tight LOL Obviously there are some serious issues here, backwards gears, passing valves and the lack of grease that should have been obvious really and luckily none of the silicone I used to stick the gasket back together had got in the pump that would have been catastrophic if id been heavy handed there of course and I know that worried him when I told him what I had to do with the gasket.
The good news is that the pump has now been fully refurbished by Arrow and as we’ve come to expect it looks amazing, better than an new OEM unit. Spending time to learn about the process means that I now know that beauty is much more than skin deep with Arrow’s work though and I can be confident about using this pump on my bike now, unlike I was (and rightly so) before.
As an aside I also had him work on a 250 pump I had. I picked it at random from a box of them that I had lying about as I’ve never rebuilt a 250 before so they just sit in their own filth in a box, poor things. When I collected it after the refurb I was shown that this very pump was a great example of just how worn some parts of these pumps can get. Here are two parts that should not have any wear... Just look at the steps!
When we measured the screw shaft wear Arrow quickly worked out that the pump was actually providing a negative stroke! Scary and probably what killed that engine perhaps leading to why it ended up in my spares. There was even wear on the pulley from where the throttle had been pinned so many times, taking these wear elements together it was deduced that it was probably off a bike that had been raced. What was especially interesting was that the bore was perfect and internally it was in great condition, yet more testament that these pumps were designed and built well; 35 years of abuse and it was still working on a machine that the manufacture never expected to have anything like that many birthdays.
Looking back at what I’ve written I see that I haven’t included many photos here... It’s a crazy fact that there seems little point putting up yet another photo of an Arrow perfectly restored pump, literally hundreds of them have already been posted by happy customers and we’ve all seen them before on the forums and my own restorations include them too. We all know they look glorious, and are just like 'yeah yeah' lol. Ok... Perhaps this pic of 3 in a group might be a little different LOL
So what have I learnt? Well... Pretty much I confirmed what I already knew that this work is best left to the professionals, especially now that we have a tame one in our midst. It cemented my view that that you cannot hope to replicate the work done by a Pro on a part so integral to the longevity of our expensive engines. Just a few minutes after meeting him, Arrow showed me his ability to look at parts and identify them as wrong for the pump in question and/or see what’s wrong with them even without measuring, he’s done that many of them now he just can tell at a glance. Spending time with him proved to me that we are very lucky to have him; his knowledge with these units is invaluable and that he has a waiting list for his services for a reason.
Often I see posts on the forums from people who want to do their own pump refurb and I (and others) always post to advise them to send it to Arrow. Sometimes they moan about the price, especially of shipping if living outside of the UK, but really this is a key component of our engines and the cost of a pro working on it is actually just cheap insurance, especially after all the big money some of us spend on cylinders and cranks. As the man himself told me, ‘The work I do on these pumps means they wont just work for another year or two, they will be good for another 30+ years’. After actually seeing what he does from start to finish, most of which you don’t see (refinishing, grease etc) or he doesn’t brag that he’s done (small mods for longevity, swapping parts for better ones in his spares and detail refinishing of edges and lapping surfaces etc), I’m not surprised by that. In conclusion, I think we are very lucky to have him, I know that I don’t want to go back to making a mess of my own pumps, I doubt you do either.