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Makotosun
Life after meltdown
- Pedalcrazy
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Replied by Pedalcrazy on topic Life after meltdown
There are specs for gap at min and max pump stroke. If your gaps are set to spec (use of shims) then the pump may be wrong one or needs rebuilt. If gaps are correct ask DEET about next steps...
1978 DT400E
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
02 Feb 2021 10:34
#111
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- msavitt
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Replied by msavitt on topic Life after meltdown
Thx
Min pump stroke 0.006” so I perhaps just a displacement issue.
Will fiddle some more, thx
Min pump stroke 0.006” so I perhaps just a displacement issue.
Will fiddle some more, thx
02 Feb 2021 10:38
#112
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- msavitt
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Replied by msavitt on topic Life after meltdown
stupid new guy question: would the addition of a 0.1mm shim increase the oil pump stroke by 0.1mm?
thank you
thank you
02 Feb 2021 12:29
#113
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- Pedalcrazy
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Replied by Pedalcrazy on topic Life after meltdown
Yes should follow that logic provided you have some gap at minimum stroke and sounds like you do. Check the spec for max stroke...don't assume if you meet the minimum you'll be good at max. I set mine pretty healthy on the upper end while not straying too far off spec at minimum.
1978 DT400E
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
The following user(s) Liked this Post: MarkT
02 Feb 2021 14:12
#114
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- msavitt
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Replied by msavitt on topic Life after meltdown
thanks
when I increase the stroke my output is not going up, it stays at 6.5ml /200 revolutions
i wonder if I missing the obvious?
when I increase the stroke my output is not going up, it stays at 6.5ml /200 revolutions
i wonder if I missing the obvious?
02 Feb 2021 15:13
#115
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- Pedalcrazy
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Replied by Pedalcrazy on topic Life after meltdown
When you have the gaps checked with a feeler gauge and are within spec (adding or removing shims) and your outputs aren't in spec then either the wrong pump or it needs rebuilt. DEET.
1978 DT400E
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
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- msavitt
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Replied by msavitt on topic Life after meltdown
Thanks Pedalcrazy, that's the situation
I have messaged DEET to get this rebuilt, i am in no hurry to melt again
Key lessons learned for my next projects (I am hooked!):
- Dont assume jettiing is proper, that she is a virgin; mine was 3 sizes too lean
- Dont assume oil pump output is proper after adjusting cables, mine was 40% too light
- While not fatal, this was exacerbated by using a plug with one heat range too hot
So to achieve what I set out to acheive - a reliable fun flashback to my youth - I am going to take my sweet ass time and get this pump rebuilt by an experienced set of hands.
Stay tuned and than you very much!
Martin
I have messaged DEET to get this rebuilt, i am in no hurry to melt again
Key lessons learned for my next projects (I am hooked!):
- Dont assume jettiing is proper, that she is a virgin; mine was 3 sizes too lean
- Dont assume oil pump output is proper after adjusting cables, mine was 40% too light
- While not fatal, this was exacerbated by using a plug with one heat range too hot
So to achieve what I set out to acheive - a reliable fun flashback to my youth - I am going to take my sweet ass time and get this pump rebuilt by an experienced set of hands.
Stay tuned and than you very much!
Martin
02 Feb 2021 17:28
#117
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- Pedalcrazy
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Replied by Pedalcrazy on topic Life after meltdown
That's good Martin that you checked the oil output! I like to keep mine on the upper end of lubrication. I told myself after break-in I'd re-visit the outputs if I thought they were too rich with oil. I am happy with the initial setups. For example...put about 1200 miles on my DT400C and when I pulled the head off to de-carbon (while I was waiting for my sleeper pipe) I was pleasantly surprised at very little carbon and No pitting from pinging. You're doing an amazing job on your bike! I'm hoping to get a DT360A....it's on the bucket list!
1978 DT400E
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
1976 DT400C
1973 RT3
1971 RT1B
1968 DT1 (3)
The following user(s) Liked this Post: Snglsmkr, msavitt
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- turbodan
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Replied by turbodan on topic Life after meltdown
One thing you might address while its easy are these little casting plugs in the stator cover. They are an artifact of the manufacturing process and can provide an air leak pathway. I gooped over mine with some sealant a little while back and today I found blue two stroke oil coming through one of the three. Yamaha applied some sort of sealant here originally but 50 years later it is likely to have given up.
03 Feb 2021 18:00
#119
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- msavitt
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Replied by msavitt on topic Life after meltdown
Turbodan - that is a great tip!
I noticed these, I think they might have been vents from die casting process. My oil pump went to Mr Deet today for a rebuild so not in a rush, I think I will pop rotor back off and coat with some sealer so I can check this box! I think I will use this amazing sealer (ElringKlinger Hi Temp sealant) I used a while back to seal a gasket-less lower oil pan on a Benz. This stuff is so tough that I bet I could have left bolts out.
I also found and bought a reasonable 1975 DT250B oil pump today on eBay today that partzilla says is same P/N that my DT360 needs. So if this has proper output I can hopefully get bike fired up while I await perfect rebuilt. If it bombs then I got a spare to rebuild for another restoration
I noticed these, I think they might have been vents from die casting process. My oil pump went to Mr Deet today for a rebuild so not in a rush, I think I will pop rotor back off and coat with some sealer so I can check this box! I think I will use this amazing sealer (ElringKlinger Hi Temp sealant) I used a while back to seal a gasket-less lower oil pan on a Benz. This stuff is so tough that I bet I could have left bolts out.
I also found and bought a reasonable 1975 DT250B oil pump today on eBay today that partzilla says is same P/N that my DT360 needs. So if this has proper output I can hopefully get bike fired up while I await perfect rebuilt. If it bombs then I got a spare to rebuild for another restoration
03 Feb 2021 19:55
#120
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