KT-17 vs MV-18

jr1712 · #1 01-24-2013, 08:36 PM

I have a 1712 with the kt 17 needs head gaskets replaced. I also have a mv 18 that I got off an old craftsman. What are the differences, the blocks, heads, ect. look the same, what makes up the extra 1 hp. I cc'd the heads and the 18 had 2 less cc's. What do the original kt 17 heads look like, does it have a pocket in the combustion chamber ,over the piston ? The 18 I konw has never been touched. It does have the pocket, compression is what I think makes up the 1 hp. I don't know if the 17 heads have been decked or not but the distance from the deck to the valve pocket on both heads are .380 ??

Any one mess with these or hot rod them any info would be great thanks.

macman81 · #2 02-02-2013, 09:08 AM

I'd love to know 2 sorry I can't help. I've heard magnums were more reliable but I don't know why.

Ihquietline · #3 02-02-2013, 09:51 AM

I believe the m18 is a pressurized oil system with our without the oil filter, the kt 17 isn't oil pressurized which with pressurized oil system engine will last longer and when on an incline will still feed oil to both cylinders. Hope this helps!

Matt G. · #4 02-02-2013, 11:15 AM

The differences will depend on whether the KT-17 is a Series I or Series II. The Series II will have a lot more in common with the Magnum, as it has full pressure lube like the Magnum does.

Ihquietline · #5 02-02-2013, 11:25 AM

Glad to know that about series 2 having pressurized oil system, I did not know that. Good info!

macman81 · #6 02-02-2013, 11:28 AM

Quote:

Originally Posted by Matt G.

The differences will depend on whether the KT-17 is a Series I or Series II. The Series II will have a lot more in common with the Magnum, as it has full pressure lube like the Magnum does.

so whats different between a kt17 series II and a magnum 18? thats what i've been trying to figure out myself

Matt G. · #7 02-02-2013, 11:33 AM

Ignition, stiffeners in case halves, flywheel, flywheel screen, and heads to name a few. Closure plate and jugs of the later Magnums are also slightly different.

macman81 · #8 02-02-2013, 11:37 AM

Quote:

Originally Posted by Matt G.

Ignition, stiffeners in case halves, flywheel, flywheel screen, and heads to name a few. Closure plate and jugs of the later Magnums are also slightly different.

so the rotating assembly is essentially the same as the series II then?

Matt G. · #9 02-02-2013, 08:41 PM

I *think* so. It's been awhile since I've messed with these engines.

JayJay · #10 02-10-2013, 10:52 PM

Quote:

Originally Posted by macman81

so the rotating assembly is essentially the same as the series II then?

macman81: Matt makes reference to "later M18" motors. I'm in the process of rebuilding an M18 right now, and I noticed references in the Kohler manual to S/N 1917809296 where they changed the cam and the angle of the valve grind from 45 deg to 30 deg. Judging from the text, this is also when they changed the design of the cylinder jugs (the early ones were interchangeable, the later ones were not).

The text of the Kohler Service Manual is also quite specific about the "Posi-lock" connecting rods; the manual goes into great detail about the differences between the Magnum rods and the rods for the K-Series, complete with pictures and arrows (see p. 10.13 of Kohler doc# TP-2204-B)

I don't know what else is different between the KT-17 (Series I or Series II) and the M18 (early and late), other than what Matt has already mentioned. And I don't know any more differences between the early and late M18's; but if I run across some more, I'll try to remember to post them here.