Engine oil for FH650

[Steven.Carter]

I've a Morgo oil filter and not been particularly bothered what 20 50 oil I've used. Changing every 1500 miles or so seemes to do the trick. My last engine done around 90,000 miles without a complete rebuild. I was trying to get to 10000 miles but got nervous. I'll report back when its in pieces for a rebuild, be interesting to see how well its done.

[JohnnyBeckett]

hi nev all motors built with a oil filter the oil goes through the filter first then into the bearings, the first 20/50 oil was done by the son of Duckhams oils he wanted a better oil for his triumph motorcycle and then they found it was better for motor vehicles engines to , Duckhams oil used my racing cars to test their new oils , and i learnt a lot about oils working with them, a lot of cars at the time suffered with sludge and stop the lifters working and block the oil pickup pipe that is how the the 15 /50 and 15 /40 and 10 /40 came about , now it is 5/30 and 5/20 and 0/20 0/30 and 0/40 and 5/40 and their is c 1 c 2 c 3 c 4 all with different additives in them and their is a lots of oils that are not suitable for air cooled engines, modern engines have become a right pain with all the different oils i must keep over 20 types of oil in the workshop now, years ago we kept about 4 or 5 grades of engine oil

[nevhunter]

The 20/50 and such are usually more needed where cold temps are encountered, to avoid the need for lengthy warmups. It's done with polymers which do wear out so the straight oils will keep their viscosity longer but it's not a problem unless you leave the oil in there for long periods.. The conventional Pump to filter to engine needs a blow off function to prevent filter blockage ruining the motor from oil deprivation. IF your tank is very clean you are nearly as well off with the filter in the return line where it's not reducing the flow to the engine. To have the filter in the USUAL position the engine must be designed for it as it's nearly impossible to do afterwards. The main thing you don't want is sludge centrifuging in the oilways where it can block them or dislodge and damage the Plain (mainly) bearings. Rollers have more tolerance of dirt, but you don't want it really, anytime. Nev

[david weare]

Hi Johnny
Yes this is my thinking. Maybe I'm being overcautious - but I what you describe is what I would expect to happen.
Best
David

HI Davei if you fit a oil filter it is filtering the oil wen it is returning to the oil tank, and not in the flow to the engine so if you have crap in the engine it has gone through the bearings before it get to the filter unless the is just been rebuilt i would just use straight oil

[david weare]

The 20/50 and such are usually more needed where cold temps are encountered, to avoid the need for lengthy warmups. It's done with polymers which do wear out so the straight oils will keep their viscosity longer but it's not a problem unless you leave the oil in there for long periods.. The conventional Pump to filter to engine needs a blow off function to prevent filter blockage ruining the motor from oil deprivation. IF your tank is very clean you are nearly as well off with the filter in the return line where it's not reducing the flow to the engine. To have the filter in the USUAL position the engine must be designed for it as it's nearly impossible to do afterwards. The main thing you don't want is sludge centrifuging in the oilways where it can block them or dislodge and damage the Plain (mainly) bearings. Rollers have more tolerance of dirt, but you don't want it really, anytime. Nev

Thanks Nev.
Filter on the return sounds sensible.
I have a little magnet in the filter basket (Revealed when you unscrew the cap on the tank) seems to collecting a reasonable amount of crud.
Which is both reassuring and worrying at the same time.

[nevhunter]

I've fitted magnets to most of my drain plugs. Make sure they can't come out. Nev