Quote from: Mick on February 01, 2021, 11:08:15 PMMy opinion.  Any oil as long as it meets the specifications should be fine.

thanks Mick - so can you vote!

And in action

Photos of the mower and the sheared key.

So I love most Honda mowers, but the OEM oil is a significant premium. So that leads me to a question!

So Mick, on my bench is this HRX537 with electric start. Leaking o-ring under the valve cover, new bbc lower bearing, new blades and new harness for starter motor to key start. Photos to follow.

So picked up a lovely 1994 Honda HR1950 with a 3-speed box at a good price. Owner complained that it was hard to start. Checked it over and indeed it took 10-15 pulls - it started and ran (badly) but wouldn't restart. Carb, coil? Then notice a slight snap back on the recoil! So after cleaning the carb, replacing a worn blade, changing a cracked tyre and respraying the recoil cover and air filter box, I decided to have a look at the flywheel key. And there's your dinner....sheared. Replaced it and she fired up magnificently. The big GXV140 purred to life... no smoke and strong drive. So just a decent service and there should be some margin in it come later this month or March.

Well Mick, there's a smokey GCV160 that needs new piston rings, a HR1950 which starts and dies....will post a few more learnings...

So I've restored this 35 year old Honda HR21-5 and replace the damaged crank (oil leak due to multiple gouges in the shaft right where the seal sits). Sonic cleaned the carb and stripped it down, resprayed with OEM paint, etc. She started first pull after rebuild. Gotta love Hondas

But in typical fashion and before I get too big for my boots, i have to admit she hunted and surged a little bit. It happened when I took the revs down but calmed down when i got to idle. If I then slowly added thottle it was fine.

I first thought the fuel/air mixture was lean so I fettled with the pilot jet screw and set it to spec (all the way in and back it off 1 and 3/4 turns). This is not a two minute job as to access the screw you need to undo the intake manifold. Anyway made no difference. So I took the carb off and cleaned it again. That's an hours job as the fuel tank has to come off as do all the linkages. A right pain. Anyway got it back together. Started hunting again.

So I then thought about the spark. I had put a new one on and it was gapped fine. But i noticed i had used a BMR6A rather than a BM6A.....could a resistor really make all the difference? Well the answer is yes it can and it did. The resistor is for non-CDI models with points and condenser. Apparently the spark is less powerful.

So it just goes to show always use the exact spark plug!   

Ok so to close this off, I found the reason the that crank seal was leaking despite changing it twice. Someone had gouged the crankshaft right where the seal lip sits. I managed to get a new old stock crank from the US (not bad for a 35 year old machine!), so swapped it out. All working fine and no more oil.

So changed the seal again. It's better but still leaking. The problem is a small gouge in the crank. Nothing will solve that other than a new crank..which I found on eBay in the US. So a winter project to swap that out. In the meantime, I'll restore the deck.

So here she is ready for sale after a good 30min test in my own garden. The hardest part was to replace the oil pan as the previous idiot had decided to use Loctite which broke the bolts. 

So Mick suggested I do a post on how I change tyres on Honda mowers. I've done a fair few HR194,214, HR21 and now this HRH. The HRH tyres from Honda are north of GBP50 but Skana and GHS do some good aftermarket alternatives for about GBP10-15.

So here's my approach:

1) Get the tyres in to some very hot water - give them 5 to 10mins
2) Meanwhile, get some grease on the top of half of the wheel.
3) Look carefully to see which way the tyre goes on (there were notches in the back of HRH wheels)
4) Remove tyre from water drain any water and dry off with a cloth.
5) get the tyre on the ground and get the bottom seated in on both sides
6) get this in a vice (the vice holding the bottom seat. Use a big flat screw driver and work the tyre over the top of the wheel. Go easy - it should not require huge force.
7) make sure all of the beads are seated correctly and remount.

Check out the video by Doublewidesix on youtube (though he goes a bit nuts with the screw driver).

So a bit of progress made. Wheels resprayed, new tyres and new bearings. Deck and under deck resprayed.

Mick, I will strip it down....and bad news, I ran her for a bit and she's leaking again. I think there is an issue with the shaft......got a couple of new seals coming. That there was 2 in there to start with means there was likely an issue.

So an update...dry as a bone under the mower so fingers crossed the problem is solved. The deck needs some love but that's a job for winter. I've changed the throttle, clutch and drive cables and the drive belt. New wheel bearings required.