Ford/NH 1715 blowby

[jetskier]

This is my first post, but I'm a long time lurker. I bought this tractor used in 2003 and it's run great until recently. I estimate the hours at around 1500, but who knows, the hour meter was changed at one point. It only reads 370hrs now. The dealer who changed it said it had around 800hrs when they changed it out for the previous owner.

For the past couple months, I've been noticing more and more blow-by on my tractor. I finally purchased a diesel compression tester. The rear cylinder measured 180psi, middle 380psi, and the front 420psi. After finishing some yard projects yesterday, I pulled the tractor into the garage and started tearing the top end down.

The first thing I noticed is some ultra fine dust in the intake. It was about 1/8" thick. I can't explain why the dust is here outside of a leaky air filter. I changed it every 100 hours or so depending on the work I'm doing. Every 10 hours or so I'd take the filter out and tap the dust off.

After getting the head off, the rear cylinder is more warn than the other two. It appears since the intake tube dumps directly above the rear cylinder, that hole got the bulk of the particles. I haven't measured the bore, but I'm hoping it's not too bad where I need to pull and strip the whole block and have it machined to the next oversize.

I guess the question is, is there an aftermarket air filter set up to use to keep this from happening again. The soil around here is sandy silt and when it's dry it's dusty. It's really fine dust.

Hopefully the measurements are within the standard bore tolerances.

 

[whodat526]

not really anything u can do about the filters but change all the orings and hoses on it but i would say u would need to have it bored out but i found out that it is cheaper to buy a pulled out motor from a salvage yard from expierence i had a 1320 that had the same problem the 3rd cyl. was bad u can pick up a complete motor for about 1500 to 2000 and the parts to fix your motor will be just about that much because there is no after market supliers for these tractor hardly

 

[Hooked_on_HP]

Is it the right air filter. Are all the seals on the filter installed properly. There are a lot of 1715's out there and have never heard of this problem.What brand filter are you using. I would check the hose between the filter and intake for cracks . As far as used engines go they are few and far between and you don't know what you are getting.
Bill

 

[whodat526]

but most reliable salvage yards will give u a 1 year warranty on the pull out motor i have bought many of them and thay gave me that garuantee call ripees' in farmington mossuri are gulf south equipment in baton rouge la. i have had 2 are three in the 15-20 series tractor it is a common problem mostly happening from running it hot but not hot enough to crack the head or a filter housing hose being cracked and sucking in dirt if u would like a price on a motor i can get u a price on a pull out

 

[jetskier]

More info. I got the pistons out. The bores are still round with little taper (within spec). The rear is a few thousands larger than the mid and front. But they are still within the standard bore limit. The pistons are worn below the minimum diameter in a few areas. One of the compression rings on the rear cylinder is worn to almost nothing. That explains the lack of compression and blow-by. All three honed nicely. There is one spot on the rear cylinder that the hone can't reach, but I can't feel it, but you can see it.

My plan is to limit the work to the top end only. So new gaskets and piston/ring kits is what I'm going to order. I think I'm going to try to find an aftermarket filter that I could adapt. The air filter that in now has been in it for about 10 hours and it's clean on the inside. My guess is one of them didn't seal or it was slightly torn. It was a NAPA filter.

I guess if I ever buy a used tractor in the future, I know one more thing to look for. Removing the intake tube for inspection takes no effort.

 

[jetskier]

but most reliable salvage yards will give u a 1 year warranty on the pull out motor i have bought many of them and thay gave me that guarantee call ripees' in farmington mossuri are gulf south equipment in baton rouge la. i have had 2 are three in the 15-20 series tractor it is a common problem mostly happening from running it hot but not hot enough to crack the head or a filter housing hose being cracked and sucking in dirt if u would like a price on a motor i can get u a price on a pull out

Just saw this. If you are willing, I'd be curious about the pull out motor. Like others have said, you don't really know what your getting.

On the getting hot issue, I've only seen it burp coolant once when I was working it hard (in 2003) after I had just bought it. I learned how to control the temps and work it equally hard. I was basically lugging it. The first thing I added was a coolant temp gauge because the idiot light is worthless.

 

[whodat526]

i know u dont know what u are getting but my family has been doing buisness with them two salvage yards for as long as i can remember and they make good on the stuff they sell but yea u would be able to tell if it was cause by getting hot it would have a scared piston and cylinder but i would check intake system for cracks

 

[jetskier]

i know u dont know what u are getting but my family has been doing buisness with them two salvage yards for as long as i can remember and they make good on the stuff they sell but yea u would be able to tell if it was cause by getting hot it would have a scared piston and cylinder but i would check intake system for cracks

That's tomorrow's task...check intake parts for cracks and holes.

 

[JFS2295]

Pretty typical of what is known as a “dusted” motor. When progressing through an intake system, dirt’s inertia causes it to concentrate into the cylinders where the intake plumbing has a straight shot, air being able to bend and curve better to the other cylinders.

Chances are it could have occurred before your ownership, and why the sale. The cartridge filters of this type can sometime fool the installer and not be fully seated. The retaining nut fits tight then during operation the filter moves into it’s proper seating position and the filter is then loose with gaps.

The hard chrome coating on the compression rings could have abraded through and then the ring would wear at a higher rate without the coating. You may have lucked out with the bores and just need pistons and rings like you state. Have you checked both the rod and main bearings? It may be possible that the dirt remained mostly in the combustion area of the block/head rather then getting into the oil wetted areas. Sounds like you’re a person who would have.

Are you using a true cylinder hone or what would be known as a glaze breaker? The most expensive hone will keep the bores true.

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[jetskier]

Pretty typical of what is known as a 髮ｻusted motor. When progressing through an intake system, dirt逞ｴ inertia causes it to concentrate into the cylinders where the intake plumbing has a straight shot, air being able to bend and curve better to the other cylinders.

Chances are it could have occurred before your ownership, and why the sale.

I'm starting to wonder this myself

The cartridge filters of this type can sometime fool the installer and not be fully seated. The retaining nut fits tight then during operation the filter moves into it逞ｴ proper seating position and the filter is then loose with gaps.

Yeah, I always wondered if it seats fully each time. I like the Ford AIS filter system I put on my 7.3L. It filters great and flows well

The hard chrome coating on the compression rings could have abraded through and then the ring would wear at a higher rate without the coating. You may have lucked out with the bores and just need pistons and rings like you state. Have you checked both the rod and main bearings? It may be possible that the dirt remained mostly in the combustion area of the block/head rather then getting into the oil wetted areas. Sounds like you豎*e a person who would have.

I think I lucked out, it appears to have remained up top.

Are you using a true cylinder hone or what would be known as a glaze breaker? The most expensive hone will keep the bores true.

Just a glaze breaker. I may have to invest in one of the true hones though.