2L into LN106... gearing issues.

[bec5175]

My partner recently had some engine "issues" in his 3L. We bought a replacement vehicle with a donor motor. After travelling 2 hours with the car trailer and looking at it, turns out it was a 2L not a 3L (the bloke selling it was a bit clueless) But given the price and the fact that we had travelled that far and that it also ran and it drove it onto the trailer...we bought it anyway. Tossed the 2L into the LN106 in a day and a half. It drives.
The issue now is the top speeds are kinda buggered up. If you ask "HIM", it revs out fine through to 4th gear, then in 5th the revs don't max out and the top speed drops to 70km/h. His mate at work told him it must be his diff ratios.
I took it for a drive this afternoon and I think the gear ratios are wrong for the motor. The gears are too long.

He just replaced the motor, left the gearbox from the 3L. The donor vehicle (also an LN106) apparently had the same gearbox, G52. Unfortunately, we neglected to take the donor vehicle for a decent drive before we dropped the motor so unsure if it had the same gearing issue. The donor vehicle was somebody's unfinished project and being an LN106 it did come out with a 3L but some goofball had put the 2L in.

So, I really just want to find out a few things. Are all G52's the same or are some geared differently? What 5 speed gearbox was standard behind a 2L or 2L-T 4WD? Is it likely to be a gearbox issue or a diff issue?

(And while were on the subject and only because i'm too lazy to go and look myself, what 5 speed gearbox comes behind a 2L 2WD in an '88 LN56?)

Cheers in advance for any help anyone is able to give.
-Bec

[lexsmaz]

I know nothing about these type engines so I googled the capacity & it and it says the 2L is around 2.4 litres & the 3L is around 2.8 litres, I think personally the engine is probably to small Now & is lacking the grunt to pull the car along in 5th gear or the 2L engine you fitted could have some issues ?? ..

You could change the diff ratio to improve it but then fuel economy is going to suffer & also your speedo is then going to be out too, as I see it you are chasing your tail rather than fixing the main problem being the engine, maybe if the motor & injection pump etc checks out ok you could Turbo the 2L motor, but again more costs ...

[bec5175]

Yes you are correct, the 2L is a 2.4 and the 3L is 2.8
We knew we would lose power but I suppose I expected it to behave differently.

I have a 2L-T in my LN56, I told him to just swap them over, but he didn't want to.

Maybe it is just that simple. He'll just have to not use 5th gear. He got pulled over yesterday for going too slow!

[SmokinSquirrel]

My suggestion is to rebuild the 3L while your partner is putting the 2L around.
If you can find the 2LT manifolds and turbo spare, they bolt straight onto the 3L head. I think also you swap over the oil coolers too, been a while since I worked with tractors
Gives you better mid range torque for climbing and highway. But with these L series, your torque dies off after 3k rpm. Theyre never gona be a racecar.