I thought i'd share a bit of what started as simple filters/oil for a tune up on my 755 but turned into a bit more. oh, by the way thanks to all the have posted about these exact items before....this place is really like having a tech manual at your fingertips for all repair stuff.
first off this is a 1989 755 with just over 1100 hrs. it was running okay, a bit difficult to start, motor rattled on start, but otherwise good.
i started with dumping all the motor oil and trans oil. I found that i had to move all the hyd cylinders to get even near the 4.5 gallons in it and that's where things got off track. to get at the filter i had to remove the lower hard line to the trans cooler up front, so i figured i'd just take both off to pull the cooler and radiator to clean them and while that was off why not pull the gas tank and drain that. so here's a picture of the front of tractor with all that removed.
while dumping the fuel i found broken fuel line, the old screen and some black tar looking stuff at the bottom. here's what that stuff looked like.
I found the hard line on the fuel pickup did not reach the bottom 5 inches or so of the tank, i imagine this is why there was so much gunk at the bottom since it hadn't been pulling anything from the bottom. another member dennisfly turned me onto this...so thanks for the tip dennis!
with the fuel tank off i cleaned all the dirt and grime off the bottom of frame support for fuel tank and repainted everything, plus all the side foam supports where gone around the tank from spilled diesel, probably causing some of the rattling at start. so i replaced all the foam and put it all back together.
moving back i checked glow plugs and took valve cover off to check valves. manual says glow plugs should be 1.3 to 1.6 ohms. 2 were bad with resistance from 20 to 200 ohms and one was good at 1.3 to 1.5. check resistance from body to threads according to the manual. I replaced all 3 even though they aren't cheap @35 bucks each. uhhh.
push rods and springs looked okay, so i just adjusted all the clearances to 0.008 per the manual and got a new gasket. it was a little difficult locating the TDC mark mostly because i didn't know where it was and the manual said it could be located in a few places. after cleaning some grease and dirt off the flywheel cover the mark appeared. checking to make sure the right valves were loose/tight at the right time confirmed the mark for me.
moving back further i found the right rear motor mount was gone and contributing to the start up rattle. i replaced the bad motor mount and then tried to replace the left mount but found the starter in the way and couldn't figure out how to get that off since the lower mounting bolt ran right into the motor mount. maybe someone could let me know how to get the starter out. here's a shot of the old bushing and new one installed.
still need to get a new battery and figure out a way to get off the floor plate to access the upper hyd. hard line to tighten that up proper. it seems there is a retainer clip on the mechanism to raise and lower the mower deck that is being a pain to get off. any trick to getting that retainer clip off would be great. i'll get a couple more photos of the machine once it's all back together. thanks for all the great info here!
damien.
first off this is a 1989 755 with just over 1100 hrs. it was running okay, a bit difficult to start, motor rattled on start, but otherwise good.
i started with dumping all the motor oil and trans oil. I found that i had to move all the hyd cylinders to get even near the 4.5 gallons in it and that's where things got off track. to get at the filter i had to remove the lower hard line to the trans cooler up front, so i figured i'd just take both off to pull the cooler and radiator to clean them and while that was off why not pull the gas tank and drain that. so here's a picture of the front of tractor with all that removed.
while dumping the fuel i found broken fuel line, the old screen and some black tar looking stuff at the bottom. here's what that stuff looked like.
I found the hard line on the fuel pickup did not reach the bottom 5 inches or so of the tank, i imagine this is why there was so much gunk at the bottom since it hadn't been pulling anything from the bottom. another member dennisfly turned me onto this...so thanks for the tip dennis!
with the fuel tank off i cleaned all the dirt and grime off the bottom of frame support for fuel tank and repainted everything, plus all the side foam supports where gone around the tank from spilled diesel, probably causing some of the rattling at start. so i replaced all the foam and put it all back together.
moving back i checked glow plugs and took valve cover off to check valves. manual says glow plugs should be 1.3 to 1.6 ohms. 2 were bad with resistance from 20 to 200 ohms and one was good at 1.3 to 1.5. check resistance from body to threads according to the manual. I replaced all 3 even though they aren't cheap @35 bucks each. uhhh.
push rods and springs looked okay, so i just adjusted all the clearances to 0.008 per the manual and got a new gasket. it was a little difficult locating the TDC mark mostly because i didn't know where it was and the manual said it could be located in a few places. after cleaning some grease and dirt off the flywheel cover the mark appeared. checking to make sure the right valves were loose/tight at the right time confirmed the mark for me.
moving back further i found the right rear motor mount was gone and contributing to the start up rattle. i replaced the bad motor mount and then tried to replace the left mount but found the starter in the way and couldn't figure out how to get that off since the lower mounting bolt ran right into the motor mount. maybe someone could let me know how to get the starter out. here's a shot of the old bushing and new one installed.
still need to get a new battery and figure out a way to get off the floor plate to access the upper hyd. hard line to tighten that up proper. it seems there is a retainer clip on the mechanism to raise and lower the mower deck that is being a pain to get off. any trick to getting that retainer clip off would be great. i'll get a couple more photos of the machine once it's all back together. thanks for all the great info here!
damien.
