RD350LC Oil Pump

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frankydee
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RD350LC Oil Pump

#1 Post by frankydee » Mon Mar 19, 2018 10:23 pm

Finishing up a complete resto on an '81. Last minute items included bleeding oil pump. Could not get oil to come out of bleed screw so I took the pump out out and apart. First thing is that the pump was full of oil so it was getting oil from the tank and the feed lines had some oil in them also (the bike had been sitting for a few weeks since I put oil in the tank and tried to bleed). Looks like bleed screw tip broken off in bottom of threads or at least that's the way it looks. Should I be able to see right into the body with the screw out? Secondly, when I pulled the pump apart, there was a small pin that looks like a small needle bearing that appeared and I am not sure of its origin.

Anyone on here know about these pumps? I cant find a diagram of a pump taken apart. I can send pics of what I have if that helps. Thanks!!

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JonW
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Re: RD350LC Oil Pump

#2 Post by JonW » Tue Mar 20, 2018 12:25 am

send your pump to Arrow, total peace of mind will ensue.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

frankydee
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Re: RD350LC Oil Pump

#3 Post by frankydee » Tue Mar 20, 2018 2:12 am

JonW wrote:send your pump to Arrow, total peace of mind will ensue.
what/who is Arrow? new here....

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JonW
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Re: RD350LC Oil Pump

#4 Post by JonW » Tue Mar 20, 2018 8:24 am

have a google or search on here for him in the members list, plenty of posts on here and other forums that (correctly) extol his virtues.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

frankydee
Posts: 5
Joined: Mon Mar 19, 2018 8:49 pm

Re: RD350LC Oil Pump

#5 Post by frankydee » Tue Mar 20, 2018 3:31 pm

OK, muddling thru this I figured out that the pin is one of two that engages the pump gear. Dont know what happened to the other one. Where can I get one?

http://www.2strokeworld.com/forum/index ... ic=15708.0" onclick="window.open(this.href);return false;

Although my pump is a little different (doesn't have white plastic gear on back) I can see I am missing a pin.

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JonW
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Re: RD350LC Oil Pump

#6 Post by JonW » Tue Mar 20, 2018 6:01 pm

you could make a pin from the end of an old drill bit, I made one for a water pump like this only last week.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

frankydee
Posts: 5
Joined: Mon Mar 19, 2018 8:49 pm

Re: RD350LC Oil Pump

#7 Post by frankydee » Tue Mar 20, 2018 8:15 pm

JonW wrote:you could make a pin from the end of an old drill bit, I made one for a water pump like this only last week.
I was thinking that but wondered if it was too brittle....

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JonW
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Re: RD350LC Oil Pump

#8 Post by JonW » Tue Mar 20, 2018 8:30 pm

You call. you could ask in the wanted section, someone might have a spare?

My feeling was that its not like these pump should be hard to spin or catch on anything. If it does end up breaking youve a bigger issue Id say...
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

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Arrow
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Re: RD350LC Oil Pump

#9 Post by Arrow » Wed Mar 21, 2018 4:05 am

There is only one drive pin in pumps of this generation. Earlier pumps had two shorter spring loaded pins. The very last of these pumps has a camshaft with incorporated drive and no removable pin.
The gear can be used on priming wheel pumps as it still has the two drive/free wheel areas. Yamaha just kept the original design with the gear, but without a priming wheel the gear only needs a single keyway (without free wheel facility) for the single drive pin.


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frankydee
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Joined: Mon Mar 19, 2018 8:49 pm

Re: RD350LC Oil Pump

#10 Post by frankydee » Thu Mar 22, 2018 11:21 am

Thank you so much Arrow. I have been beating myself up over maybe losing a pin and actually found some standard 2mm pins from McMaster-Carr. Very good information from someone that obviously knows their stuff. Nice having a place like this! :smt041

Wish I could figure out how to post pics of my ground up resto....

Hooligan
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Location: Calgary, Alberta

Re: RD350LC Oil Pump

#11 Post by Hooligan » Thu Mar 29, 2018 6:44 pm

As the oil pump is one of the most critical parts of the engine and its failure will result in an extremely expensive rebuild that will include the crank and cylinders etc. There is ZERO economy in going cheap or do-it-yourself on the pump.

Send the thing to Arrow, pay him the money and never ever worry that the pump will fail and take your expensive motor with it.

Saving $100 to risk $1500+ makes no sense whatsoever.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

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JonW
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Re: RD350LC Oil Pump

#12 Post by JonW » Thu Mar 29, 2018 7:33 pm

I couldnt have put it better myself Hooligan.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

hondaror
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Location: Alberta, Canada

Re: RD350LC Oil Pump

#13 Post by hondaror » Fri Apr 06, 2018 10:27 am

Hey Peter, good to see you posting again.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

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