Mods to a 372 xp xt

[Ronie]

Have you had a look at the piston yet? If it's not to bad you you might get away with cleaning the cylinder up and putting a new piston in it.

 

[derrick cole]

Have you had a look at the piston yet? If it's not to bad you you might get away with cleaning the cylinder up and putting a new piston in it.

Have not, just tested compression out of suspicion and sure enough she is worn out. So I figured I'd just order up a rebuild kit and carb rebuild and see how it goes from their. But figured I'd ask you experts if I should do more while it's torn down.

 

[cuinrearview]

100psi of compression low which is why I'm gonna rebuild it.

How'd it do with the 24 before?

 

[Ronie]

Have not, just tested compression out of suspicion and sure enough she is worn out. So I figured I'd just order up a rebuild kit and carb rebuild and see how it goes from their. But figured I'd ask you experts if I should do more while it's torn down.

If you put a new top end on it and want to sell the cylinder send me a PM, I might buy it depending on it's condition.

 

[derrick cole]

How'd it do with the 24 before?

It did OK but I got the saw used and it's just slowly getting weaker. Now it's getting harder and harder to start.

 

[EngineNoO9]

I'm amazed it starts with 100 psi

 

[cuinrearview]

Find the root cause of the compression loss, then do it up @Duce style. Clean up the jug, new Meteor with caber, delete the base gasket, timing advance and second port in the muffler. Buy some good files and a steak and beer dinner with the $$ you saved. Keep the chains sharp and watch that 24" spit chips

 

[Deleted member 117362]

Just cutting wood, pine mostly stuff that's up and around 24 inches. Want it to pull my full comp through which right now she is real tired.

If that saw in stock form will not pull a 24" bar and chain in pine with authority, you have a problem as others have stated. Pull your muffler and show us a picture of piston/cylinder, that saw needs a new ring or two, then vacuum checked at the least. Stock 372 should have 150psi, more or less depending on you elevation. Have done a few base gasket deletes and bumped it up 20psi.

 

[huskyboy]

X the XTORQ if it’s scored or worn out bad and fit an oem old style 372oe 50mm jug, black coil and intake tract. They run better and the price of new oem kits is very reasonable for what you get. The xtorq does have great torque and uses less fuel, makes a great work saw honestly. But I still prefer the OE cylinder if I had to pick between the two to rebuild the saw with. It’s simpler, makes great power and the bottom end lasts longer with the lighter piston. If you do decide to mod the xtorq, leave the intake strato intact. Gutting completely it just uses considerably more fuel and not much more power. Just match the lowers to the base gasket with a burr, then ditch the base gasket if possible (check squish), gut the muffler port under the deflector and cut out the division in the intake filter holder. But leave the division in the boot/carb alone. Use fuel resistant sealant for the base gasket delete. I’ve had great results from just doing this. They responded well on the 4 or so I’ve done.

 

[Brent Nowell]

I’m surprised no one is talking about the pop up piston.

What’s the quality like Ronnie? Can you get some more close ups

 

[Ronie]

I’m surprised no one is talking about the pop up piston.

What’s the quality like Ronnie? Can you get some more close ups

I'll get some more pics up tomorrow afternoon. The quality seems fine, I picked Lil Red Barn over the Hyway one because I figured that it would be made with better aluminum.

 

[Ronie]

I’m surprised no one is talking about the pop up piston.

What’s the quality like Ronnie? Can you get some more close ups

More pics

 

[derrick cole]

So would you do the pop-up VS the base gasket delete then?

 

[Brent Nowell]

More pics

Ronnie thx I was particularly looks at the ring pin quality and overall casting quality. The pins look much better than the one I bought for my poulan 3400. It also looks really decent overall.

You have me sold, what a great idea! Benefits of good squish while keeping a base gasket. Thanks for taking the time to post those

 

[Brent Nowell]

So would you do the pop-up VS the base gasket delete then?

Yes, I believe you want to stay within 20 thou, you can go as low as 15 as one other poster has mentioned but it gets dangerous.
I also believe that the whole point of allowing for 20 thou clearance from top of edge of cylinder is to allow for metal expansion. Imo you are also risking possibly detonation but I don’t know for sure if that is the case.

 

[InfiniteJest]

I couldn't find that piston on the lil red barn website. I'm a computer bonehead. Mind pointing me in the right direction?

 

[Ronie]

If you end up buying a new top end I think you should check the squish without the base gasket. If it's around .020, leave it out and use a sealant like Hondabond. With or without the gasket you shouldn't have any problems pulling a 24" bar. Cheapest cylinders I've found.

 

[derrick cole]

I ordered a new one wasn't a pop-up which I guess I'll have to regret. Will loctite 515 work or do you prefer that Honda bond. I have a muffler mod and am going to do the base gasket delete. Just gonna have to figure out the transfer matching.

 

[Ronie]

Sorry, that's not a x troq

 

[Ronie]

I use Hondabond and I've never used the Loctite. For the lower transfers just lay the gasket on the cylinder, take a marker and trace the open part of the gasket at the transfers. Then take your pencil grinder and slope the edge to where your line is. You might want to practice on an old cylinder, the burr can easily get away from you. Below is a pic of mine roughed in.