Glad to hear you found another project, I have a really nice blue 3.7A powersharp laying here myself.
By the way...... YOU SUCK!!! It has been in the 20's here this past week, though today it did get back up into the high 50's.
Roper 3.7 tear down and rebuild
- Thread starter Opihi59
- Start date
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Glad to hear you found another project, I have a really nice blue 3.7A powersharp laying here myself.
By the way...... YOU SUCK!!! It has been in the 20's here this past week, though today it did get back up into the high 50's.
Mo. Jim
Addicted to ArboristSite
Rep for the new guy.welcome aboard
Ditto................................ Although, it got to 65 here today, broke a record.
I have a nice 3.7" here with killer compression. Kills my wrist. If you really like 'em, we'll trade for that Husky. You can even put the comp. release valve back in. (it fit my Poulan 655)
R.O.F.L. (smileys not working again)
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Opihi59
ArboristSite Operative
I really like that Husky, it is a nice saw. I could part with the newer Roper 3.7 that I got as a parts saw but rebuilt since it was such a good runner. (917.353770) It just doesnt have that slim profile this XXX750 has and seems clunky to me. I still need to find a Stihl to make me feel all grown up though. I have more wood cutting to do either this wknd or next to get together a truckload of firewood all split for another Scout campout. Planny of running saws now in the pile to accomplish that task.
The Dragon Lady carried the box in the house, looked at me and said "this isn't another saw is it?" She really can't complain as I put a new Grundfos pump and a differential temperature thermostat and thermistors on our solar water heater system/replumbed the circuit last weekend so now we have hot water "off the grid" again. Anything new looking or shiny I put in last week, then put black foam insulation on it.
The Dragon Lady carried the box in the house, looked at me and said "this isn't another saw is it?" She really can't complain as I put a new Grundfos pump and a differential temperature thermostat and thermistors on our solar water heater system/replumbed the circuit last weekend so now we have hot water "off the grid" again. Anything new looking or shiny I put in last week, then put black foam insulation on it.
Opihi59
ArboristSite Operative
I just got another Roper in the mail, craftsman 917.353762 which is identical to the .XXX750 featured in this thread, only noticeable difference is that it has the "save your knuckles" kickback protecter shield mounted on the wrap hangle. This one was an ebay saw and needs the clutch cover. One of the bar studs was bent, and the ends of the threads were boogered up by someone forcing a pair of 8mm X 1.25 pitch bar nuts on when the proper size is 5/16 24TPI. I managed to straighten the bend without cracking my case half, and re threaded the studs. This saw has outstanding compression, the piston looks great and the cylinder is literally perfect. The fuel line had rotted off inside the tank but it ran with fuel down the carb very easily. I've already separated the case halfs and put it back together with new fuel line, did the usual tear down to clean and inspect everything and I couldn't find anything worth replacing. Will switch to a dual adjustable carb so no plans on rebuilding the current carb. When I get the photos downloaded I'll post some up but it really is the same saw for all intents and purposes to the original star of this thread.
Opihi59
ArboristSite Operative
So here's the latest, I tore down the "new" 3.7 and went thru it. I split the case halfs (tank) and put them back together, re-assembled the saw and the tank leaked. Saw did run though and I was going to work on that further but the tank was leaking. I haven't had problems in the past sealing case halfs, or any of the various applications on my Jeeps where there are no gaskets but RTV silicone is used instead. I took the tank apart, re sealed it and let it sit but tested it with raw gas this time. It leaked significantly. I went around the seam but found the seam wasn't leaking. There was an unnoticed crack at the base of the channel where the bar adjuster block runs. This saw had taken some sorta impact here, I had found that the front bar stud was bent back some, etc but had straightened and re-threaded that. In the second photo below, you can see the stud bent backwards a bit, this is pre-repair. So here are a few photos of course of the latest saw/challenge.
Next few may seem nebulous, but this is the channel that the bar adjuster runs on, just below the bar studs. I have a pointer on the beginning of the crack and it runs about half an inch to the right from there.
You will notice you can see the impression of the square bar adjuster slide in there, and I feel there is a similar matching crack opposite this one that I can't demonstrate very well. The dilemma of course is the best option for fixing this crack as it obviously took some sorta whack here. First off, I plan on letting it dry and blowing out the cracks with air, then "caulking" it with some of that Yamabond and working it into the crack with my finger. The sliding block that rides in the channel could rub this seal away though, so I can grind some clearance off the back of the adjuster block, and of course the block rides back and forth on the adjuster screw and not against the back of the channel per se. I could also cut a thin metal shim and lay in the base of the channel on top of the yamabond to prevent wear against the silicone as well. More I think of it it seems to be a reasonable idea. If anyone has any thoughts on this, I'd be happy to hear them. Either that of someone with a buncha spare case halfs laying around.
By the way, the repair I did on the damaged case of the first saw featured in this thread is doing fine. I gummed on a dab of Yamabond, let it cure, then shaved it down a bit.
Next few may seem nebulous, but this is the channel that the bar adjuster runs on, just below the bar studs. I have a pointer on the beginning of the crack and it runs about half an inch to the right from there.
You will notice you can see the impression of the square bar adjuster slide in there, and I feel there is a similar matching crack opposite this one that I can't demonstrate very well. The dilemma of course is the best option for fixing this crack as it obviously took some sorta whack here. First off, I plan on letting it dry and blowing out the cracks with air, then "caulking" it with some of that Yamabond and working it into the crack with my finger. The sliding block that rides in the channel could rub this seal away though, so I can grind some clearance off the back of the adjuster block, and of course the block rides back and forth on the adjuster screw and not against the back of the channel per se. I could also cut a thin metal shim and lay in the base of the channel on top of the yamabond to prevent wear against the silicone as well. More I think of it it seems to be a reasonable idea. If anyone has any thoughts on this, I'd be happy to hear them. Either that of someone with a buncha spare case halfs laying around.
By the way, the repair I did on the damaged case of the first saw featured in this thread is doing fine. I gummed on a dab of Yamabond, let it cure, then shaved it down a bit.
OldRoper
New Member
Wow!!
Someone must have run this poor thing over. The compression has mine beat by 30psi. Coincidently, I just completed resealing mine using a tank epoxy from caswellplating.com
(GTS1750 for $40), and for the first time in about 10 years, the tank does not leak.
If you chose to go this route it may be a problem since it cannot be air shipped. I received mine in 2 days.
After fishing out the fuel line, removing the filter & pickup ass. and plugging line with a screw:
The prep was a tank flush with ACETONE, a wash with hot soapy water, dry, coat with the mixed 2 part epoxy, remove excess, and cure for 36 hrs at 80f or above. The stuff dries clear and is hard like a rock. There is no apparent reaction with the original coating in the tank.
The beast cranked right up and ran fine, and has not lost a drop of fuel in 2 days.
Someone must have run this poor thing over. The compression has mine beat by 30psi. Coincidently, I just completed resealing mine using a tank epoxy from caswellplating.com
(GTS1750 for $40), and for the first time in about 10 years, the tank does not leak.
If you chose to go this route it may be a problem since it cannot be air shipped. I received mine in 2 days.
After fishing out the fuel line, removing the filter & pickup ass. and plugging line with a screw:
The prep was a tank flush with ACETONE, a wash with hot soapy water, dry, coat with the mixed 2 part epoxy, remove excess, and cure for 36 hrs at 80f or above. The stuff dries clear and is hard like a rock. There is no apparent reaction with the original coating in the tank.
The beast cranked right up and ran fine, and has not lost a drop of fuel in 2 days.
Opihi59
ArboristSite Operative
I will hold off a bit on doing a repair, whatever method I go with I will likely plug the various tank vent holes/fuel line holes and pull a vacuum thru the fill-port while I apply the gunk of choice to the outside of the tank so it will pull whatever thru the crack rather than just laying on top of it so to speak. It's not anything I need to be in a rush to repair, it's just got to work with the first option I go with.
I can always separate the tank halfs again to get to a repair site on the inside of the tank, but it would have to be something that will tolerate constant soaking in gas. Not real keen on spending $40 for what you used then whatever boat trip it requires to get out here--that's my equivalent of "ground" shipping.
Glad you got your tank leak issue solved.
I can always separate the tank halfs again to get to a repair site on the inside of the tank, but it would have to be something that will tolerate constant soaking in gas. Not real keen on spending $40 for what you used then whatever boat trip it requires to get out here--that's my equivalent of "ground" shipping.
Glad you got your tank leak issue solved.
Opihi59
ArboristSite Operative
Didn't come up with another plan, so went ahead with my Yamabond idea. I cut a piece out of an aluminum can. Seems these type drinks have a heavier gauge aluminum than your standard can. This one was 0.020" thick.
Cut to fit in the bottom of the channel for the bar adjuster block.
I put a gob of Yamabond in there, worked it into whatever cracks, then sucked a vacuum on the fuel fill port while plugging off vent hole, fuel line, etc, then after a few mins of that put the shim in there and smoothed it out.
Since the shim took away from the depth of the channel, I ground approx 0.022 thickness off the block, then beveled the sides so it doesn't act as a gouge and chew out the yamabond in the edges of the channel. That's the block in my grubby black Yamabonded fingers.
I will let that cure a few days before I test it with raw gas. Raw, that way if it leaks I don't have to struggle getting oil out of the crack to do another bond technique. Will let you know how this works after I test it out. It seems good in theory, but then again, I've messed up things that made real good sense more than once in my life.
Cut to fit in the bottom of the channel for the bar adjuster block.
I put a gob of Yamabond in there, worked it into whatever cracks, then sucked a vacuum on the fuel fill port while plugging off vent hole, fuel line, etc, then after a few mins of that put the shim in there and smoothed it out.
Since the shim took away from the depth of the channel, I ground approx 0.022 thickness off the block, then beveled the sides so it doesn't act as a gouge and chew out the yamabond in the edges of the channel. That's the block in my grubby black Yamabonded fingers.
I will let that cure a few days before I test it with raw gas. Raw, that way if it leaks I don't have to struggle getting oil out of the crack to do another bond technique. Will let you know how this works after I test it out. It seems good in theory, but then again, I've messed up things that made real good sense more than once in my life.
Looking good there. Did you get that other Roper you messaged me about? I tired to reply but it told me your box was full.
Opihi59
ArboristSite Operative
Yes, I did get it. It's on the slow boat so I'll likely have it in my hands in about 3 more weeks. I plan to use it as a parts saw only, so that means I should have some parts to share around from it. I am sorry that my mail box was full, I need to go thru it As Soon As Possible and knock out some space there. Seems the mailboxes fill up real fast, and the only way I know is someone tells me.
Ha! The yellow one missing air filter cover and broken oil tank?
You outbid me by fifty cents.
http://www.ebay.com/itm/130631462775?ssPageName=STRK:MEDWX:IT
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Opihi59
ArboristSite Operative
Nope, not me
No, I didn't bid on that one. It was a Red Roper Craftsman without a starter/starter cover, bar/chain or an air filter cover. I'll make sure though that if I am looking at one I am interested in, I'll also make sure that either you or Roanoker are not bidding as well. It makes no sense for me to compete against colleagues when we make a practice of sharing parts from the spoils.
It was this one: eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices
Ha! The yellow one missing air filter cover and broken oil tank?
You outbid me by fifty cents.
No, I didn't bid on that one. It was a Red Roper Craftsman without a starter/starter cover, bar/chain or an air filter cover. I'll make sure though that if I am looking at one I am interested in, I'll also make sure that either you or Roanoker are not bidding as well. It makes no sense for me to compete against colleagues when we make a practice of sharing parts from the spoils.
It was this one: eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices
Opihi59
ArboristSite Operative
Runner!!
That latest saw is running, and real nice too. I swapped carbs on it since the pulse feed didn't seem to be good on the other (bad D/G kit) so I will rebuild the Hi/Lo tunable Tilly carb I have for it and toss that on next. Parts saw inbound on the slow boat for some missing pieces. For now, I have to cut back on saw purchases since I just packed my roof with photovoltaic panels. I am now a power company, and my meter is spinning backwards. Woo Hoo!!
That latest saw is running, and real nice too. I swapped carbs on it since the pulse feed didn't seem to be good on the other (bad D/G kit) so I will rebuild the Hi/Lo tunable Tilly carb I have for it and toss that on next. Parts saw inbound on the slow boat for some missing pieces. For now, I have to cut back on saw purchases since I just packed my roof with photovoltaic panels. I am now a power company, and my meter is spinning backwards. Woo Hoo!!
ChainsawmanXX
Addicted to ArboristSite
.
One of the saws I was most surprised by.. Its a blast to run!
You are not alone, many have been shocked by these little saws abilities. Very nice power to weight ratio to be a old cheap saw.
Craftsman 917.353770
Have this old chain saw. Has sentimental value for me being dad's..
Can I ask for help and advise....The carb needs replacement, and I am thinking is there a carb
out there that would fit into this saw BUT that it has both H and L adj. screws. The old carb.,
and there is one of its flaws, only has the idle adj. screw and Low speed mixture screw.
Maybe there is a newere model carb with both adj screws that would fit.
If not, any info as to where a repairs parts kit and gasket kit can be found.
thanks a mil.
Have this old chain saw. Has sentimental value for me being dad's..
Can I ask for help and advise....The carb needs replacement, and I am thinking is there a carb
out there that would fit into this saw BUT that it has both H and L adj. screws. The old carb.,
and there is one of its flaws, only has the idle adj. screw and Low speed mixture screw.
Maybe there is a newere model carb with both adj screws that would fit.
If not, any info as to where a repairs parts kit and gasket kit can be found.
thanks a mil.
Opihi59
ArboristSite Operative
Your 917.353770
I have a very nice running one of those, it is also a Roper 3.7 but is a newer model than the .XXX750 featured in this thread. It's a good saw, and since it has sentimental value to you it's worth whatever effort you put in it. I prefer the 750 style in the Ropers since they seem more compact, less wide/bulky, but that's just my personal bias.
They are very easy to tear down and work on, they also have plastic gas and oil reservoirs, they use the same motor as the 750 with the same crank seals, same piston/rings. I also considered putting a dual adjustable carb on mine, it comes with a Tillotson carb and an RK 23HS rebuild kit will work for it.
A dual adjustable carb like a Tillotson HS79A would be a carb you could use with this feature, however take the top off your saw--the mechanism of the trigger and configuration of the box would not allow a space for the adjustment screw for the high mix screw. Remember I have one of these saws, I also thought about upgrading exactly like you, but with the parts in hand and the saw on my bench I saw it would not be a beneficial process. That doesn't mean it cannot be done. Look at your saw, find the low speed mix adjustment, then look for the dimple about 1/2" rearwards on the carb body--that's where the High speed mix adjustment would go. You would have to cut off the "screw" so it would clearance the shaft/lever assembly (trigger wire hooks to that) and cut in a new screwdiver slot. To access this for adjustment though, the trigger lock is right in the way, you would need to drill a hole thru the side of the airbox where you could reach this screw to turn it, and come up with a plug to then cover the hole in the airbox so you don't suck debris into your carb thru it. So go back up to the first photo, look at the location of the low speed adjustment screw, and you can see the trigger lock and idle adjustment screw is practically right where the high speed adjustment screw would come, if you did shorten the high speed screw so it would fit behind the trigger lever, and you'd have to have the saw running almost wide open for that to rotate out of the way while you try to come in sideways to try to adjust the screw. Yes, can be done. Is it worth it? Only you will know for sure. I didn't bother to modify mine because of this awkward arrangement in the trigger/trigger lock mechanism. I just put in carb rebuild kit, new rings, new crank seals, sparkplug, gas and oil and ran the you know what out of it. Good luck, and welcome to the forum.
I have a very nice running one of those, it is also a Roper 3.7 but is a newer model than the .XXX750 featured in this thread. It's a good saw, and since it has sentimental value to you it's worth whatever effort you put in it. I prefer the 750 style in the Ropers since they seem more compact, less wide/bulky, but that's just my personal bias.
They are very easy to tear down and work on, they also have plastic gas and oil reservoirs, they use the same motor as the 750 with the same crank seals, same piston/rings. I also considered putting a dual adjustable carb on mine, it comes with a Tillotson carb and an RK 23HS rebuild kit will work for it.
A dual adjustable carb like a Tillotson HS79A would be a carb you could use with this feature, however take the top off your saw--the mechanism of the trigger and configuration of the box would not allow a space for the adjustment screw for the high mix screw. Remember I have one of these saws, I also thought about upgrading exactly like you, but with the parts in hand and the saw on my bench I saw it would not be a beneficial process. That doesn't mean it cannot be done. Look at your saw, find the low speed mix adjustment, then look for the dimple about 1/2" rearwards on the carb body--that's where the High speed mix adjustment would go. You would have to cut off the "screw" so it would clearance the shaft/lever assembly (trigger wire hooks to that) and cut in a new screwdiver slot. To access this for adjustment though, the trigger lock is right in the way, you would need to drill a hole thru the side of the airbox where you could reach this screw to turn it, and come up with a plug to then cover the hole in the airbox so you don't suck debris into your carb thru it. So go back up to the first photo, look at the location of the low speed adjustment screw, and you can see the trigger lock and idle adjustment screw is practically right where the high speed adjustment screw would come, if you did shorten the high speed screw so it would fit behind the trigger lever, and you'd have to have the saw running almost wide open for that to rotate out of the way while you try to come in sideways to try to adjust the screw. Yes, can be done. Is it worth it? Only you will know for sure. I didn't bother to modify mine because of this awkward arrangement in the trigger/trigger lock mechanism. I just put in carb rebuild kit, new rings, new crank seals, sparkplug, gas and oil and ran the you know what out of it. Good luck, and welcome to the forum.
Opihi59
ArboristSite Operative
More on your Roper .XXX770
Your saw will tear down real easy for clean up, just a few "exploded" shots.
This should be the carb you're running, honestly I'd just rebuild it and run it like you stole it. If/When Roanoker drops in on this thread and renders advice/opinion, I'd go with what he says. I always do. These experts know what they are talking about!
Your saw will tear down real easy for clean up, just a few "exploded" shots.
This should be the carb you're running, honestly I'd just rebuild it and run it like you stole it. If/When Roanoker drops in on this thread and renders advice/opinion, I'd go with what he says. I always do. These experts know what they are talking about!
Opihi59
ArboristSite Operative
OOPS!! Sorry forgot the carb photo, duh.
