Does anyone know goes next to the oil sending switch on the block of a 3B? it is a threaded hole about 2 1/2 inches towards the front of the motor right in front of the oil switch. The right thread and size would be nice.
There is a low oil pressure switch and an oil pressure sender for the oil pressure guage in that area. Some engines simply have a plug there. If it's the plug you are missing, I have extra ones. The thread size is metric but closely resembles 1/8" NPT, it is NOT the same though. If you use a brass or other soft metal with a 1/8" NPT thread it should go in but don't blame me if you strip out the block.
Once Cruiser_guy gives you the correct size, you should be able to pick up the fitting from a Japanese tractor parts desk. I went all over Abbotsford a year ago looking for a metric fuel injection fitting for my aux filter assembly. Even the fuel injection shop and the Mercedes diesel shop didn't have it. The Kubota tractor dealer was the only one who had the metric fitting. They had just about every type and size of metric fitting there.
It's 1/8 BSP not npt. Some have been able to get npt to work. I have not but you can get bsp adapters for $5-7, Mcmastercarr, napa and other places can be found. I think there is a part number in the forum if you search.
I had a 1/8" steel fitting that I could not get to work and since it was steel I was not about to force anything. I also had a brass fitting with the same thread and I was able to get it to work. That's where my turbo oil supply is coming from for the FJ45LV/3B. I'll be keeping an eye on it to see if there is any leakage occuring.
Any good quality gear oil will work. With the price of fuel I use synthetics because they are a little slipperier and give a little better mileage. Was the tranny overfull and the transfer underfull? If so you need seals too or the bypass hose.
John, I can't remember where I got it in Canada. I did get most of my oil at the Shell bulk station on Marine Way and Boundary or at the one in New Westminster just off Braid near the freeway. As for the price, I don't remember that either though I know it is not cheap. $12/liter is about what it cost here in Guatemala for Castrol Synthetic. I'd think it would be less in Canada.