Zed Head

I used it until I picked up a very worn ZX 5 speed, then I went to a mysterious controversial blend (SWEPCO 201 w/ATF). MT-90 works great in good condition transmissions. It even fixed a 3rd gear high RPM grinding problem in a 1978 5 speed, over plain old Valvoline 75W-90 gear oil. I used my leftover MT-90 in my Pathfinder 5 speed. Works great there too.

Thanks for adding. Hope I'm not blowing up biodi's thread. It looks like the servo synchro problem has been confusing people for many years. Found another old thread that suggests improper fluid can cause problems. SWEPCO raises its head again, JMortensen's favorite from his Porsche days. Maybe the Redline MT90 isn't the best for this transmission? Who knows. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=508611 p.s. I think that baulk essentially means "stop", which is what the rings do in a relative way. So both servo and borg warner style should both be baulk rings. People seem to be using "baulk" to differentiate. Anther confusion.

Odd - http://www.partsbase.org/parts/nissan-c010022500/

What's the pressure plate number? Just for reference. And, maybe, at least, you can get the right pressure plate for the odd disc and have a set. We all like pictures too, if you have them.

How long has it been since it last ran? Results from cold dry cylinders may not be very representative.

That's the thought. I'd use a momentary switch, button or rocker, so that you couldn't leave it on accidentally. Being down in TX though, you will probably rarely need the CSV. And Megasquirt probably has a Start enrichment function that adds fuel during starting, by adding injector open time. You might check the documents.

I've pondered just using a priming button. A squirt or two per start. Like pumping the gas pedal on a carb with accel pumps. After a few starts you'll know what it needs. Seems like the same could be done with the injector circuit. They probably used a separate valve to allow better vaporization before the cylinders. I only think about it because I've recently discovered that my battery is weak. Cold weather starts were more difficult and I have no CSV. A battery charge helped, of course, but it got me thinking.

I don't want to pile on. But, Mobil seems to be avoiding the whole yellow metal issue entirely. They've written their documentation in a vague way, that leaves the question unaddressed, directly. Just saying, you're probably fine. But Mobil is not going to say, one way or another. Corporate baffle-speak. http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Syn_Gear_Lube_LS_75W-90.aspx

I added my SWEPCO file to the Downloads area. You should add your OilTek file. More info is always good.

That's a good find and an interesting paper. Unfortunately, and I hate bring out my inner cynic, it's somewhat typical of what a consulting firm will produce for a customer. It seems to address an issue but doesn't really get there. Lots of pages, but questions still unanswered. Seems to support the products of the company that paid for the report. Page 17 is the page we'd all look at for the "yellow metal" issue in manual transmissions, the synchros. But they use a copper corrosion test. Yellow metals would be alloys of copper, not pure copper. Alloys have different properties than their components so the copper test doesn't really mean too much. Also, a synchro undergoes high speed friction in use, so a simple chemical attack test would not be the best indicator of potential problems. Still, worth reading. Just add a grain of salt. Here's an old paper, attached. I found that actually calls out the "yellow metal" problem. Same issue though, it's written by the company selling the product. Here's another interesting thing - the Royal Purple product that failed the copper test, Royal Purple Max-Gear 75W-90, is called out specifically in their ad copy as okay for GL-4 manual transmissions. Hard to imagine that they would do that since it opens them up to all kinds of liability. So, in the end, we're all still wondering. http://www.royalpurpleconsumer.com/products/max-gear/ SWEPCO GL4 and 5 TG_199508.pdf

Could really use a better description of what happened. What you were doing, what the wiper motor was doing, how you were testing, what exactly you did just before it stopped working... You have a really unusual problem so I'd guess that absolutely nobody on here has ever experienced it. A guess would be that you kept pressing the button on the stalk, which activates the washer motor, and a certain number of wipes of the wipers. How many times did you press the button, what happened when it stopped, etc. Are you saying the the wiper stopped working when you pressed the button, or stopped working completely even when you turned the wiper switch. Unclear. Could be that you just burned out a relay or timer. Have you been in to the FSM yet? There are many diagnostic procedures in there.

I should have looked at more pictures. There's a Nissan FS5C71B 5-speed gearbox in the link below. Might have parts and know some potential buyers. Kind of far away though. http://lescollinsracing.com/transmission/gearbox

By the way, it doesn't seem that your rebuild kit will work, so that question might be answered. And your rebuild guy now knows more arcane Datsun transmission stuff.

So is the consensus growing that this is a Nissan Competition 5 speed with the tail shaft converted to slip-yoke? Still need the ratios to be more informed. Thanks for the puzzle. Found some more links. http://www.datsunroadster.com/PIC_PAGES/PARTS_INFO_PAGES/synchro_info.htm Doesn't look like a Roadster box - http://www.datsunroadster.us/PIC_PAGES/PARTS_INFO_PAGES/transmission_types.htm Here's a Comp box for sale, with the flanged tail - http://510forsale.blogspot.com/2009/11/1969-datsun-pl-510-road-race-car-for.html

Cool. I missed that one too. Doesn't look like the "case cover" is threaded. Looks crimped, so probably not unassemblable.

Found this today. Posted the larger picture in a different thread. Page EC-21 1972. Percolation is a bad thing, I think.

A timely post, re the Panama problems. I looked back to where I found a drawing of the thermostat placement and find also that Nissan has a check procedure. Made a copy. It's in the 1972 FSM, page EC-21. I didn't find anything in 1973 though, and the Parts Manual shows it as disappearing in June of 1972. Maybe that's Build date.

Found some old CZC.com threads on the steel Porsche-style, and actual Porsche factory, synchro topic. Haven't figured out if it's just the synchro/baulk ring or if you need the gear/cone that goes with it too. Steel and brass might not be interchangeable. It looks, though, that the gear ratios might tell if you have a Competition transmission. The ratios can be pretty tight 1st to 5th. Might not even be suitable for the way you plan to drive. Here's one example, not sure if they're all like this. 2.906 / 1.902 / 1.308 / 1.0 / 0.864. 2.906 would need something like a 3.9 diff, which would make the .864 5th a 3.37 overall. Compared to a .864 with a 3.54...3.06. Just playing around in your thread. Good luck.

They look like steel on my computer. A brush with some Scocthbrite would remove any tarnish. But they'll be out and on the bench soon anyway. The outer part of the teeth is thicker also in the pictures, both here and my ratsun link. Almost like tops have been machined down. Pretty sure I saw a post from JMortensen about machining Porsche steel synchros to fit the Datsun transmissions. Don't know where Datsun gets their steel synchros. It's an interesting puzzle.

Still weird that your guy couldn't tell steel from brass. Oh well. Note the conversation on the Competition transmissions in that link and the different ratios. John Coffey probably knows what you have there. Might reply if you sent him a message.

Groovy! Looks like steel, not "black fiber" (who coined that term anyway?). Found an old thread with pictures. Edit - modified the link so that it can be opened. something weird gonging on. Change the space between community and ratsun to a . community ratsun.net/topic/51601-5-speed-id-help/page-2

The thing I circled? It shows up in the pre June 1972 diagram. Looks a lot smaller though. #38 http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-240z-260z/manifold/to-jun-72

C'mon Bart, haven't you seen the problems that other people have had. Are you implying that they're all idiots? One good, many bad. It's simple calculation of the odds.

Hot. http://www.weather.com/weather/tenday/l/Panama+City+Panama+PMXX0004:1:PM