Topic: Maui Z1 1973

[MauiK3]

When I have the pump I ordered in hand I’ll compare them. Before I take it apart to inspect I’ll try my messy bucket test to see if there is any visible difference, not scientific but it may be informative.
I’m also going to try to see how much side clearance the oil pump gears have with the gasket installed, maybe plastigauge. if it looks like a lot I may lap both the pump body and cover and install the cover with no gasket and a tiny film of sealer. Only if the pump gears have sufficient side clearance. This may improve pump efficiency and output.

[Terry in Australia]

I reckon that the pump is doing it's job Steve, and I wouldn't waste my time pulling it apart again until the "new"(old) one arrives. I think there's a blockage (or a restriction, at least) somewhere between your oil pressure light switch and the cams.

[Terry in Australia]

I got all excited and decided to fire up my Z1-B that’s been sitting since March. The battery was dead flat, so it’s on the charger, but as the nicer weather is heading my way, I’ll have to re-do the shims after the cam changes and plumb in the oil cooler lines so I can ride it.

[craz1]

Just a thought, when you installed the oil filter is it the right sequence. The spring should go on first then the washer then the filter. Make sure the rubber filter seals are in place and have not slip out. When I install the filter I spin it on over the threads otherwise pushing it on can dislodge those rubber seals.

[MauiK3]

Good point.
I’m also going to have another look at the base and head gaskets to see if they are the culprits.

[PeWe]

About the oilfilter. Same on CB750, the filter seals need to be oiled so the bolt can glide thru without seal coming off.

[Terry in Australia]

Well I charged up the battery on my hotrod Z1-B over the last couple of days. I thought I'd try kick starting it but I forgot that I could never do that so I kicked it thru a couple of times with the ignition off and hit the button, and Varoom! Away it went! Crappy 6 month old fuel wasn't playing well in the high comp big cam engine, but as it warmed up it'd let me give it a rev, and I pulled the clutch in to free up the plates, and I could snick it into first gear without it wanting to complain, so that was good. It started to rain again so I decided not to go for a lap around the block on the green tyres, but I was very excited that it still runs awesomely, and as soon as the weather improves I'll see what I have to do to get it legally on the road.

For your info Steve, when started from cold and idling at 1500 RPM, the oil pressure guage (I don't run a light, and seeing your previous post about your light going out when no oil was getting to the head, I won't now) was reading 12 psi, and as it warmed up to "Warm enough to ride" temps (It runs pretty hot due to the high compression) it gradually dropped to around 2 psi. My oil pressure gauge is marked in increments of 3 up to 15 psi, so 2 was a guess, but just a little under the 3 mark, so I'll call it 2. That was with the bike sitting upright. (with me sitting on it)

While it was running I had a few little drops of oil appear under the engine which annoyed me, I'll need to see where that's coming from before I take it for it's roadworthy test.....

[PeWe]

There is a pickup to suck oil from the pan on this bike, right? If that somehow will fail.

My nearby shop made trap doors to ensure oil during accelerations on Z1-900, 1000 to I suppose.

Is it possible to flip base and/or head gasket wrong so oil passage is covered? Or the oil pump gasket.

Interesting oil pressure difference.
CB750 70-80 PSI at idle when started cold. 40-60 PSI when cruising in 4000rpm (100kmh/60mph)

Good design with lower pressure which must avoid leaks

[Terry in Australia]

Yep, the beauty of a roller bearing crank Per, no need to squeeze oil thru tight orifices, and although it's "low pressure" it's also "High volume" so plenty of oil is moved around the engine. I ran oil pressure gauges on my Suzuki GS bikes too, and can remember sitting at the lights with the gauge reading zero psi, but the engines didn't miss a beat.

[MauiK3]

Interesting, 12 psi, I didn't think it would go that high. My replacement pump is on the way. I'm going to check the base and head gaskets again as I re-assemble again.
I even looked at the screen on my current pump, it's new and I compared it to the old rusty one, they are the same.
I'll get a photo of some wear I noticed in the oil pump housing, not sure it's significant. The oil pump gears clearance to the housing is just over 0.002", a 0.0025" feeler gauge does not go in.

[Terry in Australia]

As I’ve said since I saw your video Steve, I’m pretty sure that your pump is fine, we’ve seen it moving oil up higher than the cams in that tube, so it definitely works, we just don’t know how well. My pump certainly hasn’t been loved like yours, I didn’t even pull it apart.

[RAFster122s]

https://www.thedrive.com/news/honda-has-been-quietly-making-old-kei-truck-parts-for-years

[craz1]

You need a 15psi gauge as the pressure runs 6-9 psi depending on hot or cold, some may get sown close to 4psi.

[Terry in Australia]

Most Z1 owners wouldn't have a clue what oil pressure they're running, as very few run a gauge, as it's "Not original". I must admit that the only bike I don't run an oil pressure gauge on is my K0 because I couldn't get one during the Covid lockdowns which affected postage in and out of Oz in 2020 (no bike shops around here sell oil pressure gauges) but as I haven't had any issues with the bike in the 3000 miles that I've done on it since December 2020, I probably won't bother installing one.

[Terry in Australia]

Steve asked in another thread for a video of my Z1-B running so he could see the oil pressure. Today was a magnificent day but I had a ton of little jobs that I needed to do, culminating in my making a valiant attempt at mowing my rain soaked lawn. I was lucky I was wearing gumboots, the yard was super sloppy after the rain we've had lately, but Spring is on the way, and as previously mentioned, today was probably the best day we've had this month.

I decided that a quick and dirty lap on the Z1-B was in order. I'd bought 10 litres of fresh gas so I syphoned as much as I could of the old crap out of the tank to run my mower, and tipped in 5 litres of 98 RON, that had a few ml of fuel system cleaner added. As usual the bike started immediately (gotta love the Dyna 2000 ignition and new RS34 carbs) and as soon as it fired up I pushed the choke in and let it settle into a lumpy idle. I remembered that Steve wanted to see a vid so I just let it idle as it was pretty cold and hadn't warmed up. In hindsight I should have blipped the throttle to show the increase in oil pressure, but I was too excited about finding my helmet, changing out of my gumboots and going for a lap.

I only went for a short ride, but it's an absolute beast, I gave it some stick in second gear and the front wheel came up off the ground a little and once past around 5K RPM it went absolutely crazy, and wouldn't have too much trouble keeping up with some of my modern bikes. I better finish it off, (will definitely do a valve clearance check after seeing some pics on FB of a guy whose mint Z1-B spat a shim and smashed the casting on both his head and cam cover) I need to plumb the oil cooler, remount the horn to clear the oil cooler, and I think it's just about right to go for it's Roadworthy Inspection. I've also ordered a new pair of YSS rear shocks and a new chain as I'm worried about snapping the cheapie 630 that I originally put on it.

   

[MauiK3]

I've got the pump I ordered, I may take it apart to compare with the original just to see if there is anything different.
Thank you for the oil pressure video.
More to come

[MauiK3]

Well.....now I have two oil pumps, they measure almost exactly the same no matter how I check them, so it must not be the oil pump. Now I'll look again at the base and head gaskets. Even though my "feather test" showed air flow it may not be a good test, there may be a slight blockage causing a path of least resistance scenario. The confounding problem continues.

[PeWe]

You'll check for eventuak blockage along the oil's entire path from pump to head?

I really hope you will find something that explains the problem that you fix and ride in piece on that fantastic bike in paradise!

[Terry in Australia]

It’s always sounded to me that it wasn’t your pump, I wouldn’t be surprised at all if there’s a big dry lump of silicone hiding somewhere in the cylinder block or head, left over from a shoddy repair back in the day?

I suppose the next test is to do your cranking test again with the head removed and the cylinder block bolted down to see if oil is moving thru the oilways from the oil pump to the top of the cylinder block? That’s what I’d do, any way.

If the oil is travelling to the top of the block as it should then it’s either the head gasket, or the head. Yes you’ll need to make some tubular spacers to go over some of the studs with nuts on top (I used some aluminium tube I found at my hardware store when I was doing something similar to work out how much to trim off the pistons on my 1428cc engine when I installed the GPZ1100 head) and you’ll need to hang your cam chain so it doesn’t get caught around the crank sprocket, but it will further exclude (or pinpoint) the cylinder block as being the culprit, or, if oil os flowing as it should, will point the head out as being the problem.

Oh, and if you want to recoup the cost of your Ebay oil pump I need one for my Z1 engine build.

[RAFster122s]

Oops, not very intelligent to swim or snorkeling in murky areas...
https://www.foxnews.com/us/shark-hawaiian-island-bites-french-woman-leaves-her-critical-condition.amp

[Terry in Australia]

Oops, not very intelligent to swim or snorkeling in murky areas...
https://www.foxnews.com/us/shark-hawaiian-island-bites-french-woman-leaves-her-critical-condition.amp

I think that's called "Victim Blaming" David. Like most tourists, she would have seen the glossy brochures of blue seas and sandy beaches, but I bet there weren't too many signs saying "Big fcuking sharks live in the sea and like eating tourists"......

[RAFster122s]

Well, ignorance not withstanding, any shark attacks in the islands often get hushed in the media as it is bad for business.
Sharks live in the sea, if you are going to be in their habitat you are wise to understand conditions that put you in greater risk. To me that is common sense. I weigh the risks I take when swimming and snorkeling as well as when riding.

[Terry in Australia]

Ha ha. I bet you do David, but not withstanding your incredible analytical skills, some folks think that it’s ok to go to Hawaii and go for a swim. As much as you can’t blame the sharks for mistaking a French woman for a domestic seal, you shouldn’t blame her because she apparently swam in murky water, she’s probably not an expert on shark attacks.

[MauiK3]

Shark attacks happen here and they usually make the news. This is the big ocean and stuff happens.
We have a beach here with a big shore break called “Big Beach”, the life guards are always warning the swimmers to be careful. This beach is known for breaking people badly. Do they pay attention? Not always.

Shark attacks are well documented here on radio etc. that murky water is not a good place to be, tourists hear the message and often ignore it. Many tourists ignore lots of things, they are on vacation, they have spent lots of money and feel they are entitled. We have a sometimes short term rental near us and the stuff the visitors do can be very rude, we are the folks that call Maui Police when they get out of hand too much. Loud party at 2 am? Yep.

[Terry in Australia]

Ha ha, well if I was David I’d probably say that it’s your fault for living there Steve! But you’re right, some tourists (not all, I’ve been a tourist from time to time and don’t feel like I acted irresponsibly) don’t put a lot of thought into behaving themselves when they’re away from home.

My oldest boy regularly travels to Bali for work and can’t believe how badly the tourists (especially Brits and Aussies) treat the local people, it’s almost as if they’ve decided that because they can afford a holiday in one of the cheapest tourist traps in the world they are entitled to talk down to the poor locals who rely on tourist dollars just to survive.