GF1800 Timing..etc.

[bcomstock15]

Hello, I bought a GF1800 (which i dont see mentioned much on here for some reason) (D722 engine, 200 hrs) It's an out front rear steer 18HP model, little guy. The last owner had straight water in the cooling system and let it freeze outside. This basically is my first time doing any repair work beyond routine maintenance on anything, so please bear with me.

Problems Caused:
-bulged radiator bottom, lifting it into contact with the engine cooling fan
-cracked thermostat housing
-popped frost plug in gear case (Grey oil)

Q's:

-I had to remove one of the gears to put in the new frost plug. I'm worried that the gears are not sitting the same way they were when i removed it (timing issues?) i see some marks (dots) and I'm wondering how to line these up/calibrate them properly.

-Also, what other problems do you think might have been caused by the freezing? i haven't taken the head off yet, not sure if i should check in there (for frost plugs or whatever).

-Once all is said and done, how do you recommend cleaning out the coolant holding area of the engine? i can see its quite rusty inside.

The tractor was running well enough to load it on the trailer and drive it into my shop when i bought it.

Anything would help, i've included a picture of the current set up (which i believe is close to what it was when i removed the large middle gear)

Thank You.

 

[eserv]

Remove that center gear and reassemble so that all the marks are satisfied and you will be Golden. each gear has a different number of punch marks, they need to align with the appropriate number of marks on the center ( idler) gear.
as far as damage done, you might be VERY lucky or you might need a new engine! get it running again and you will soon know.
Ed

 

[birddogger]

It is a little bit more complex than that. I'm gonna suggest what eserv said is right, but it needs done at top-dead-center. If there's no mark on the gear on the crankshaft you need to find the TDC mark on the flywheel. Then line up the match-marks on the cam gear and injector gear with that idler gear.
I'm betting the cam gear jumped when you pulled the idler, because it is showing in-time and the injector gear is way off. If you are turning the crankshaft and meet firm resistance, STOP, that means you have valve/piston interference from being out of time. Cushy resistance from compression is no worry.

 

[eserv]

It is a little bit more complex than that. I'm gonna suggest what eserv said is right, but it needs done at top-dead-center. If there's no mark on the gear on the crankshaft you need to find the TDC mark on the flywheel. Then line up the match-marks on the cam gear and injector gear with that idler gear.
I'm betting the cam gear jumped when you pulled the idler, because it is showing in-time and the injector gear is way off. If you are turning the crankshaft and meet firm resistance, STOP, that means you have valve/piston interference from being out of time. Cushy resistance from compression is no worry.

Of course, you are right Birddogger! I work on these tractors every day so it is easy for me to just assume others would be aware of certain things.

 

[birddogger]

Just re-read and noticed, this is a mower. So perhaps someone can point the direction to the TDC mark. I been thinking tractor the whole time.

 

[bcomstock15]

Interesting stuff, the term top dead center is definitely a new one to me. The tractor was running before, and once warmed up no smoke or anything, sounded perfectly normal (i have another one of these to compare), its just that after about 5 minutes of running the temperature started going up quickly, so id shut it down.

Anyways, Ive been taking pictures along the way, and i found one that i took BEFORE i removed that center gear to access the frost plug, so these were the original settings when i got the tractor. So should i just match it up exactly as it is in this picture? or is it a good idea to calibrate it?

I'm not sure if it would be qualified as a mower.. i call it a tractor since you can put various attachments on it etc. I've attached a picture of it in case some of you aren't familiar with this model.

-Brandon

 

[bcomstock15]

Hi birddogger & eserv, i was hoping i could get a bit more input from you guys or anyone else regarding this issue, my parts should be in tomorrow and i plan to start working on it then. I appreciate what Ive gotten from you so far, and thank you.

-Brandon

 

[birddogger]

Wow. I had squeezed in a reply between the outage periods but I guess it didn't get through whatever confusion was happening.

It looks like from the last picture of the gears it did in fact stop very close to TDC. If you can get it back to like that last picture. Then, if it is equipped with glow plugs pull the one closest the gears. Get a plastic probe, I use a plastic coffee stirrer stick or about 5 inches of SOFT copper wire; no hard metal or wood. Let that probe down gently through the glow plug hole and come to rest. Rotate the crankshaft just a tooth or 2, watch your probe. Use that stick to tell you if it is truly TDC or not. Bring it to TDC, meaning the probe will be highest. You will get a situation where you turn the crankshaft more because it didn't seem to move, then it lowers...oops, went past TDC, go back the other way till it lowers again then split the difference and find the highest spot. Confirm that the marks on the left and right gear (injector and cam gears respectively) are truly lined up with the idler gear. Do all this with the idler gear locked in place with the clip. Unclip and adjust the gears if needed. PUll out the probe and reinstall glow plug.

That's the hard way. The new picture is oily, but it almost looks like there is a timing mark at 6 o'clock on the idler gear. If there are 3 marks on the idler line them up with, injector gear (left), cam gear, and crankshaft. If they marked the crankshaft too it's a breeze. If not the you have to find TDC as above.

The frustrating thing is I could have finished it in the time it took me to type this. No fault of yours'. If I was in your neighborhood I would have done it for fun, typing isn't fun.

Oh, for clarification TDC. Piston at Top, a line through the crankshaft, through the connecting rod big end, through connecting rod small end goes Dead Center through them all.

 

[bcomstock15]

So.. i just finished ( i thought ) put the engine back together, back in tractor, filled up the fluids.. etc. and.. won't fire.

It turns over like crazy, but wont fire up, a couple of (i think) weird things are happening: no smoke from muffler, but lots of suction?!? white smoke comes out of the air filter when its turning over, and i took the oil cap off, when i put my hand over it there is no pressure or suction or anything whatsoever.

Any ideas what i did wrong? i thought maybe i hooked up the wires wrong, but i checked all of them in the video i took before dis assembly, the only one i couldn't confirm was where one that connects to the positive end of the battery goes, i connected it to the starter is this correct?

Thanks guys.

 

[birddogger]

Suction at the exhaust pipe? Is that what you meant? that would mean it is out of time badly. The last picture you had showed only a tooth or 2 away from timing. Did if fall right back into place like that last picture?

 

[bcomstock15]

Hey Birddogger, Yes, suction at the exhaust pipe.. seems like its running backwards, sucking air in the exhaust, and smoke out the intake. fk. I followed your instructions (i think..) with using the markings on the gears.

There was one mark on the bottom of the idler, which i matched up with the one mark on the crank shaft.

There was a three mark on the left of the idler, matched w/ injector.

There was a two mark on the right of the idler, matched w/ cam.

I matched them up exactly (touching) which wasn't quite how it was from the factory as you can see in the picture, the injector and cam gears are 2-3 teeth off touching marks.

In hindsight i guess i should have just matched it up with the picture from factory.

I can't see the mark on the crank shaft in the picture.. but i assumed its 1 mark should be at 12 o' clock touching the idler's 1 mark and 6 o'clock

Thanks again for your help.

 

[birddogger]

This has me really scratching my head. If you set up the timing marks, set at idler to crankshaft, idler to cam, idler to injector; that is the way it goes.

There is usually only one heavy wire from the battery near the starter, and that should go to the + positive terminal of the battery. If there are 2 heavy wires there maybe you did get them mixed up and the unit is spinning backwards. If you have a volt meter, put the (red) + lead from the meter on the starter motor terminal (big terminal), and the - (black) from the meter to the frame and see if the meter says -12 volts or + 12 volts. It should show + 12.
With the plunger type solenoid it is possible to engage the starter backwards. A Bendix type would spin but not engage.
After all this lets hope it just a mixed up wire.

 

[bcomstock15]

I really hoped i was dumb enough to just have the wires switched but that's not the problem.. I guess it must be a timing thing, but i made damn sure that i connected the dots..

I'm wondering why the dots weren't connected from the factory? why would they leave them a few teeth off? (is this the answer to my problem?)

It is that the dots are suppose to be connected (touching) right? i didn't read into this incorrectly?

there is quite a bit of pressure coming out of the intake when its turning over too.. aaaarggg!!

Anyone have any ideas i can try to pursue before tearing it apart again? or is it basically narrowed down to the gears not being placed properly?

 

[bruceatlam]

When you have "all the dots lined up" do you also have #1 cylinder at top dead center -- sounds like it's 180 degrees out ---- that would mean that #1 is at bottom dead center when you have all your dots lined up.

 

[eserv]

I really hoped i was dumb enough to just have the wires switched but that's not the problem.. I guess it must be a timing thing, but i made damn sure that i connected the dots..

I'm wondering why the dots weren't connected from the factory? why would they leave them a few teeth off? (is this the answer to my problem?)

It is that the dots are suppose to be connected (touching) right? i didn't read into this incorrectly?

there is quite a bit of pressure coming out of the intake when its turning over too.. aaaarggg!!

Anyone have any ideas i can try to pursue before tearing it apart again? or is it basically narrowed down to the gears not being placed properly?

If you take it apart again you will find the dots don't line up anymore. you would have to turn the engine a lot of times before they would all come together right. The idler gear is just that, an idler gear, it is not a mathamatical multiple of the other gears. the crank gear and the cam and inj. pump gears are. ( The crank gear has exactly half as many teeth as both the other gears do)
Ed

 

[bcomstock15]

When you have "all the dots lined up" do you also have #1 cylinder at top dead center -- sounds like it's 180 degrees out ---- that would mean that #1 is at bottom dead center when you have all your dots lined up.

I didn't follow the TDC instructions given to me by birddogger (stupidly), because everything had dots on it, so i thought i could simply line them all up. the idler gear has one dot on it, as does the crank, so i put the cranks dot at 12 o'clock, and the idlers at 6 o'clock so that they were touching, i assumed it was that simple..

 

[bcomstock15]

If you take it apart again you will find the dots don't line up anymore. you would have to turn the engine a lot of times before they would all come together right. The idler gear is just that, an idler gear, it is not a mathamatical multiple of the other gears. the crank gear and the cam and inj. pump gears are. ( The crank gear has exactly half as many teeth as both the other gears do)
Ed

Eserv, I feel like a real dope now. Its beginning to make sense, what is the purpose of having these marks all over the idler gear then, if not to calibrate the gears to it (this is what ive been doing wrong all along?) or is it that i dont understand how the calibration works? are the dots supposed to be touching (ex. one at 6 o'clock, the other at 12 o'clock) or something else?

Thank You all for the time your putting in here.

 

[birddogger]

Yeah, that's what has me scratching my head. Normally with those marks aligned you are done, can't get any better. Unless the mark on the crankshaft was really just a ding or manufacturing artifact and not really the timing mark. Was it a solid pip like those on the other gears?

 

[eserv]

Eserv, I feel like a real dope now. Its beginning to make sense, what is the purpose of having these marks all over the idler gear then, if not to calibrate the gears to it (this is what ive been doing wrong all along?) or is it that i dont understand how the calibration works? are the dots supposed to be touching (ex. one at 6 o'clock, the other at 12 o'clock) or something else?

Thank You all for the time your putting in here.

Hi bcomstock,
I sent you a PM for a service manual for your tractor. Please let me know when you have it.
Thanks!
Ed

 

[bcomstock15]

Yeah, that's what has me scratching my head. Normally with those marks aligned you are done, can't get any better. Unless the mark on the crankshaft was really just a ding or manufacturing artifact and not really the timing mark. Was it a solid pip like those on the other gears?

Yeah, it was a mark for sure. It was even painted yellow lol (the only one painted).

I'm probably going to tackle this thing again today.. when i put the newgasket on, i rtv'd (permatex ultra copper) both sides with as thin a layer as possible. That gasket is probably unusable now huh? do you think the rtv was a wise decision?