| Author | Message | ||
     Buellistic |
BUELLers: The oil pump is a two stage pump... One side pumps the oil out of the sump(with a little help from crank case pressure) to the oil tank... The other side(with a little help from the pressure in the oil tank and gravity) sucks the oil out of the oil tank, pushing it through the oil filter to the tappets, rod bearings, and every thing else that is pressure fed... SO HERE GOES: There is no way to filter the oil that the pump sucks out of the sump... Therefore any metal or otherwise is pumped into the oil tank... This stuff is then sucked through the other side of the oil pump to the only filter on the front of the engine... HERE IS WHAT "i" DID: Installed an oil filter(small auto one) in the return line to the oil tank... This will keep the metal or otherwise from going through the feed side of tthe oil pump... This should cut the wear $ failure rate by 50%... BUT, on models that have the -98 oil pump there is another PROBLEM... IT IS: There is a slot under the pump drive gear which sucks the oil out of the cam gear area... The PROBLEM is there is no screen over this slot... Any metal or otherwise can(and has) get into this slot and cause the pump to self destruct... Usually it causes excessive drag or locks up and the pinion shaft oil pump drive gear self destructs as it is softer metal than the oil pump drive gear... Have a -98 oil pump in my 97S3T and will be addressing the problem soon!!! Will keep the board posted on how it was corrected(made screen)... In buelling LaFayette | ||
| Blake |
Cool! Take pictures?  BTW, is the '98 pump also used on Sportsters? | ||
| Buellistic |
Blake: Did take pictures!!! Have to get developed when all on roll taken... Do to the fact that HDI $ BMC have PART NUMBER IDENTY PROBLEM the the -98 pump might also be a -91A in HDI... In buelling LaFayette | ||
| Aaron |
all 91-97 Sporsters & Buells used 26204-91 all 98-99 Sportsters & Buells used 26204-98 (larger scavenge section) all 00-03 Sportsters & Buells (except XB9) used 26204-91A (same large scavenge section as 26204-98, but some differences in the porting) all '03 Firebolts use 26357-02 (internal parts appear to be the same, fittings are different, not sure on housing) | ||
| Buellistic |
Aaron: BUT, still no screen over the slot that scavenges cam gear area!!! In buelling LaFayette | ||
| Aaron |
There's also no screen in the inlet that scavenges the crankcase. It can suck shrapnel into the pump through that port, too. Particularly after a top end craters on ya. Inlet screens ain't a bad idea, but really what you're talking about is limiting the damage after something has already failed. | ||
| Buellistic |
Aaron: Remember O'TOOLs LAW: Murphy was an Optimist!!! There were inlet screens on the K-Models to the XL-Models(ie:52 to 58)... 59 was the last time that "i" had an XL engine completly apart... Some where afterwards the enginers started to leave out these inlet screens... Even the BIG TWINS had them... Something small like part of a tooth off a cam gear in the engines of the past would keep on going... You would never know about it until the engine was taken apart after many miles... "NOW" this shows up right away with out the inlet screens!!! In buelling LaFayette | ||
| Buellistic |
Aaron: Was just looking in my OLD XL MOTORS MANUAL!!! It had a CRANKCASE BREATHER VALVE SCREEN(ie: between flywheel area and oil pump... Also was a CRANKCASE OIL STRAINER in cam gear area... THE OLD ENGINERS DID NOT PASS ON THE STRAINER RULES!!! In buelling LaFayette | ||
| Crusty |
The old engineers also had a trapdoor that allowed easy access to the transmission. | ||
| Buellistic |
Crusty: The 1952 K-MODEL did not have a trans trap door... From 1953 to current year "EVO SPORTSTERS" have a trap door... "LONG LIVE THE TUBE FRAME BUELLS" There are THREE REASONS that the XB9R's, XB9S's. and BLAST's do not have a trans trap door... The engine is lighter, the engine case's are stronger, the case's are cheaper to manufacture... The minus is the same as the 1952 K-MODEL!!! It cost's BIG$$$$$$$ to fix transmission when the whole engine has to be removed and taken apart!!! In buelling LaFayette | ||
| Aaron |
I can point to SEVERAL things they've cost-reduced over the years and made less desirable in the process. Everything from splined pinion shafts to removable isolator plates. | ||
| Buellistic |
Aaron: And those of us that can improvise can get around all those negative things, "BUT", the average customer is at a LOSS $$$ In buelling LaFayette | ||
| Buellistic |
Aaron: Found out that the screens between the flywheel area/oil pump and cam gear area/oil pump have not been in the SPORTSTER engines since 1976... "WHAT A MISTAKE!!!" In buelling LaFayette | ||
| Rick_a |
I thought the first "real" Sportster came out in '57. |
