Low compression on KE70 need parts source

[bolensg154]

I want to rebuild my KE70 2cyl Bolens G154 iseki
Where can I get Piston, rings oversized pistons???
Head gasket.....etc....

Has anyone tried using other available pistons, boring to match.
Hardest part would be finding wrist pins to match.

 

[fxrs55]

how long have you had this tractor? are you sure what is wrong with the engine
that is causing the low compression? I ask because when I got mine it had no
compression in one cylinder and almost none in the other. I was able to fix
mine without new rings or pistons. I did buy a new head gasket and other
Mitsubishi engine parts like valve seals and valve guides from this place.

Small Import Tractor Supply - Home

I have also bought parts from a member here " Lens12 "

https://www.japanesetractorparts.com

 

[bolensg154]

Thank you I will call them.

 

[bolensg154]

My dad purchased this tractor new in 1978
It just slowly lost power while mowing the lawn about 14 years ago. After thinking it was out of fuel I checked the tank, it had fuel to the pump but nothing out of the pump. I put in the barn and it sat for 14 years,
two weeks ago i pulled the injector pump and injectors and had superior diesel go through it and test the injectors,all good except it wont start.
I checked the compression and both cylinders are 150 and 125.

 

[fxrs55]

My dad purchased this tractor new in 1978
It just slowly lost power while mowing the lawn about 14 years ago. After thinking it was out of fuel I checked the tank, it had fuel to the pump but nothing out of the pump. I put in the barn and it sat for 14 years,
two weeks ago i pulled the injector pump and injectors and had superior diesel go through it and test the injectors,all good except it wont start.
I checked the compression and both cylinders are 150 and 125.

read this thread.

http://www.tractorbynet.com/forums/iseki/273164-bolens-g154-iseki-tx1300f.html


when i got my tractor it had sat for well over 15 years.
it had no compression in one cylinder and very little in the other.
read what i found wrong with mine and what i did to fix it.
It now still runs very good and starts easy every time.
My rings were stuck in the pistons, the valves were not
sealing well when fully closed on the valve seat and so on.
check that thread before you start throwing money
at yours.

 

[Ilikeurtractor]

As fxrs55 stated always start with the easy/cheap fixes first. At some point though, you will invariably need to address a low compression problem which may only be remedied by new rings and/or pistons. I just went through a KE70 and trying my hardest to keep costs low and doing the minimal I ultimately ended up boring it out. The piston to cylinder clearance was approaching 0.020" in some places. The new pistons could actually be inserted partially into the cylinder, skirt end first before boring. I tried honing and new rings for the original pistons first which I have successfully done in the past on other engines with little gain. The rings were supposedly changed shortly before I bought it too and upon disassembly I found a broken top ring on the #1 cylinder which appeared to be caused from the rather thick ridge that wasn't removed before installation of the new rings. I thought if I fixed that I would be good. Blowby was horrendous on the engine. You could actually see smoke rising during starting up through the head with the valve cover off. Also found a bent rod on that cylinder which ended up being straightened in a press (not ideal, but works).

I ended up buying parts from NCW tractor because I found their prices to be the most competitive and I never had any issues with their parts working. Be advised though that new pistons from them for the KE70 have recessions in them that look similar to valve reliefs equating to about 4 cc of volume. Running some quick numbers, if the engine was designed at 20:1 compression this 4cc of additional volume will lower the ratio to 17:1. I'm not sure how hard it is to find oversize "flattop" pistons.

 

[lens12]

I can supply Mitsubishi parts, aftermarket parts, or I have good used engines.

 

[Ilikeurtractor]

Thoughts on cylinder honing and re-ringing:

G154 cylinder bore condition and hone - YouTube

Continuation:

G154 hone and new rings - YouTube

 

[HomesteadOC]

Thoughts on cylinder honing and re-ringing:

G154 cylinder bore condition and hone - YouTube

Continuation:

G154 hone and new rings - YouTube

Any updates on how the rings are working with coolant and covers back on? I have a 77 Satoh Beaver S370D KE70 0.7L diesel with possible ring issues. It didnt sit as long (6mo), but my compression is low #1 275psi, #2 300psi. Seller says it just wouldnt start one day. I put some lucas oil and ATF down the glow plugs to try and free up any stuck rings and Im just waiting for that to work in and save me. Most people say I need a re-ring, but if the re-ring is going to give mediocre results, then I might just opt for a complete overhaul. In your videos I cant really tell, but Im assuming you pulled the rods and pistons out from the bottom without removing the engine. How much easier is that than pulling the engine? Seems like a knuckle busting party with oil in the teeth laying under there. Did you try a can of restore before the tear down? Im thinking thats my last resort before a hone and re-ring.

 

[lens12]

Rods and pistons come out the top without removing the engine. Once head is removed cylinders can be measured to see if just rings will work or if it needs to be bored. I have a couple used KE70 motors that are in good condition.