K161 Tear Down

[WHX?? 48,777]

Got a chance to tear down this 7 HP this weekend. Obvious some one has been in it before with the .030 piston & plastic guv gear and  few other odd things. 

The piston was seized in the in the bore but not real tight and loosened up fairly easy. There did seem to be alot of back and forth play in the rod big end at TDC/BDC. 

I was pulling the crank pully and she locked up again but then while pulling felt something let go.

Pulled the the base to find this. I believe the piece of wire laying next to the dipper is from the retaining thingy from the rod cap bolt retainer. One side is missing and the cap bolts were somewhat loose. Definitely not torqued to what they should have been but rod was still tight on the journal. 

Damage to the rod does not matter as the crank needs to be turned as it has rod aluminum on it. But what caused the dipper to break? 

 

If this engine is ever going to be serviced under rod is in order. I have yet to do any measuring. Dan thought if this is an under crank it might be stamped as such on the cap? There is some numbers on the rod so more investigation is in order. 

 

Not sure what the fate of this girl is pending a 161 that Kev @pullstart has for me. Maybe a rebuild for a shelf spare for the 753 that smokes like a bandito possibly? 

 

Did find out what what going on here and should have guessed the cam pin was under there. Turns out the cam pin was very loose and slid out without any effort. 

 

Bore & piston looked fairly decent but again no measurements yet. Possibly clean up with the ball hone??? Note the antiseize on the head bolts so somebody knew.  

Edited August 31, 2020 by WHX24

[Achto 27,503]

8 minutes ago, WHX24 said:

Did find out what what going on here and should have guessed the cam pin was under there. Turns out the cam pin was very loose and slid out without any effort. 

 

So your saying that the "custom" wrench has to stay?? I knew it was put there for a reason.

[WHX?? 48,777]

5 minutes ago, Achto said:

 

So your saying that the "custom" wrench has to stay?? I knew it was put there for a reason.

LOL it will just for aesthetics and so other guys can  if nothing else!  Kev was right it is covering a hole in the block! 

The cam pin issue will have to get fixed so cam turns on the shaft and not the shaft in the block. 

Edited August 31, 2020 by WHX24

[Pullstart 62,789]

It was probably an old 15 mm... nothing to possibly use it on a WH other than hold a snubber in place!

[Achto 27,503]

6 minutes ago, WHX24 said:

LOL it will just for aesthetics and so other guys can  if nothing else!

 

Might have to send it out for re-chroming.

[WHX?? 48,777]

1 minute ago, Achto said:

send it out for re-chroming.

Oh lord no.... and wreck that patina!?!?!? I figured it would stand out against shiny new red! 

[WHX?? 48,777]

Another oddity....main bearing with a shield to the inside???  Same on both ends. 

[WHX?? 48,777]

Not really an oddity but something I have not seen before. Fuel pump drives off the cam lobe that is offset! I expected this pump to be a pulse style as my other 161's.  I first thought now how did the lever get bent like that!?!? Then I took another swig and it dawned on me! 

Edited September 1, 2020 by WHX24

[WHX?? 48,777]

External resistor???? There was none! Maybe this is why ( or the rod knock) retired this old girl.

[Achto 27,503]

22 minutes ago, WHX24 said:

External resistor???? There was none!

 

Did it by chance have a resistor wire? They do make a resistor wire to be used in place of a resistor.

[WHX?? 48,777]

4 minutes ago, Achto said:

 

Did it by chance have a resistor wire? They do make a resistor wire to be used in place of a resistor.

For the 12 volt feed or the plug wire??? I don't know I just cut it off and canned it. Plug wire is long gone. Speaking of plugs the plug hole is stripped out but I might be able to save it. I should have one of these anyway. 

https://www.amazon.com/gp/product/B0009OMYCO/ref=ox_sc_act_title_2?smid=ATVPDKIKX0DER&psc=1

[Achto 27,503]

4 minutes ago, WHX24 said:

For the 12 volt feed or the plug wire???

 

For the 12v feed. I would just chuck that coil & get one with an internal resistor any way. The tread chaser may cure the plug hole but if it is stripped out you made need to have an insert put in it. A common heil-a-coil doesn't often work.

[WHX?? 48,777]

2 minutes ago, Achto said:

I would just chuck that coil 

Already chucked ... bashed in the back anyway from the hokey mounting bracket. 

[ebinmaine 67,274]

2 hours ago, WHX24 said:

under crank it might be stamped as such on the cap?

Normally it would be stamped on the cap of the rod but could also be on the crank itself. Heard of both....

 

[oliver2-44 9,684]

3 hours ago, Achto said:

 

 if it is stripped out you made need to have an insert put in it. A common heil-a-coil doesn't often work.

@Achto  School me on why a heil-a-coil doesn't often work for a spark plug fix?  What other type of insert could be used?

 

[pfrederi 17,664]

I have used this twice.

[Achto 27,503]

48 minutes ago, oliver2-44 said:

@Achto  School me on why a heil-a-coil doesn't often work for a spark plug fix? 

 

A common Helicoil does not seal properly. You also run the risk of the coil coming apart and falling into the cylinder. A plug hole repair insert will seal and can never fall into the cylinder. Below is a proper thread repair for spark plug holes.

 

https://www.autozone.com/test-scan-and-specialty-tools/thread-repair/oemtools-14mm-spark-plug-rethreader-kit/265137_0_0?spps.s=1970&cmpid=LIA:US:EN:AD:NL:1000000:TLS:71700000060668368&gclid=EAIaIQobChMIg9-bmY_G6wIVjsDACh3KmgfxEAQYBCABEgIjdfD_BwE&gclsrc=aw.ds

Edited August 31, 2020 by Achto

[oliver2-44 9,684]

Thanks Achto. 

A few years ago I installed an insert in the head of the k301 on my Case 180.   I got lucky and bought the one you show that has a top lip on the insert so it can't go through the head. Now I know what to look for in the future and not rely on luck

Edited September 1, 2020 by oliver2-44

[953 nut 55,075]

20 hours ago, WHX24 said:

Another oddity....main bearing with a shield to the inside???  Same on both ends. 

I ran into that on a couple of K-241blocks a few months ago. Did a tear down on three of them, none of them appeared to have been apart before. I found the shield turned in on two of them. I guess enough oil would get by to lubricate the bearings.

[WHX?? 48,777]

39 minutes ago, 953 nut said:

guess enough oil would get by to lubricate the bearings.

Dan and I thought the same thing here Richard. It's interesting to know that it appeared the motors were built like that then. Possibly an oil control method to keep the seals from seeing too much oil???? 

This motor it seemed that the bearings were loosely fitted on the crank journals. 

If I do rebuild this one I would use a build kit with the new bearings in it. 

 

So in my fuel pump research I fitted a standard fuel pump to the 753 while waiting for Buckrancher's pulse pump diaphragms to arrive. He just PM'ed they went out in the mail today 

I did get some gas to move through it but not enough. Now I know why. This 7 HP also has an offset pump lobe on the cam so a large bore motor pump will not work. Thus the need for the pump with the offset arm or pulse style. 

It would be interesting to know if the other small bore motors,91 & 181, have the pump cam lobe offset from the centerline of the pump mount. Just guessing they do but if someone just happens to have one open please verify this for us. It can be checked through the mount hole with a bright flash lite. 

Edited September 1, 2020 by WHX24