Stump the Experts, 184 style(FIXED)

Thu Sep 13, 2007 6:55 pm

This is for the Experts to diagnose. I brought a 184 Lo-Boy home last night to work on for a fella. He seemed to be pretty knowledgable when I asked him things he's done to it. Anyways, it won't start and hasn't started for nearly a year. It's been setting in his barn. He used to mow grass with it and states: I could mow for nearly an hour, then it would just up and die and wouldn't start till a few days later, then mow again for awhile then die again and no start. I brought it home to trouble shoot it. Now it has me scratching my head after 4 hours of tinkering with it.

1) It has great compression on all 4's, nearly 120psi.
2) I installed new plugs
3) Changed condensor
4) filed and set points
5) checked and rechecked timing. no 1 on compression TDC mark aligned on the pulley
6) I found alittle play in the dist shaft at the point end, thinking maybe it was causing the gap to fluxuate. I installed the whole dist out of the trencher Cub(also 12 volts). No Go, still won't start
7) switched carbs, installed the carb off the trencher Cub that runs perfect, still nothing
8) switched caps and wires and rotor, still no start.
9) checked firing order 1,3,4,2 clockwise rotation for dist setup.
10) plenty of gas flowing through the sediment bowl and into the carb, both carbs that I tried.
When I pull the plugs, they are slightly wet. After I'm done cranking, gas runs out the carb weep hole for about 10-15 seconds and quits.
I dried off the plugs and plugged the wires on each plug, layed the plugs on the maniflod loose, then cranked the engine. Each plug has a nice blue spark.

I've rechecked the rotor several times bringing number one up to TDC(compression) and each time, it's right on.

The last thing I did was pull the intake/exh manifold. The outside nuts weren't very tight but the center nuts were. After pulling it off, you could tell the center of the manifold was leaking. It just seems the engine should have popped, spit, backfired, at least did something, but nothing, just spin fairly fast with no signs of a fire.

Any suggestions would be greatly appreciated. I thought I could figure this thing out in short order, but the jokes on me :shock: I have to order the manifold gaskets before I can continue.

Thanks,
Rick
Last edited by Rick Prentice on Mon Sep 17, 2007 6:31 pm, edited 1 time in total.

Thu Sep 13, 2007 7:04 pm

Coil?

Thu Sep 13, 2007 7:07 pm

Rick, you seemed to have covered all the normal areas. I'm thinking the gasket is leaking since over time, the heating up/cooling down which will cause things to shrink & contract may be allowing it not to pull the fuel into the chamber? Have you tried shooting ether into it to see if will start that way?

Thu Sep 13, 2007 7:07 pm

Don McCombs wrote:Coil?

Thu Sep 13, 2007 7:11 pm

I can even give you the NAPA part number. :D

IC14SB

Thu Sep 13, 2007 7:11 pm

Oops, Sorry, Yep, switched the coil when I swapped the dist off the trencher.

I even jumpered a wire from the battery+ to the + side of the coil to make sure it wasn't a switch some place.

Rick

Thu Sep 13, 2007 7:14 pm

Rick - when you checked the timing did you just check the pulley mark against TDC or did you also verify the rotor position as well? You have fuel, fire and compression - it has to be a timing issue.

Thu Sep 13, 2007 7:15 pm

Just wondering, when you crank it, is there spark at the plugs? I'm thinking along the lines of one of the "safety over-ride" devices being bad and not allowing current to flow?

Re: Stump the Experts, 184 style

Thu Sep 13, 2007 7:17 pm

I could mow for nearly an hour, then it would just up and die and wouldn't start till a few days later, then mow again for awhile then die again and no start.


First part sounds like a weak coil.

Check the valve tappet clearance. Check for valve operation - condition of the springs, keepers, stems.

Manifold gaskets.

Take a timing light and check for spark during cranking on each cylinder.

Another guess. Your 180 degrees out of time. Finger in #1 plug hole double check.

Vacuum guage check if it still doesn't start.

Eugene

Thu Sep 13, 2007 7:28 pm

Rick - when you checked the timing did you just check the pulley mark against TDC or did you also verify the rotor position as well? You have fuel, fire and compression - it has to be a timing issue.

Yep, each time I removed the plug, rotated the engine until compression was felt, then aligned the mark on the pulley(the TDC mark, not the 16degree mark) then removed the cap and verified the rotor was indeed pointed at number one on the cap.

I cranked the engine to note the correct rotation of the rotor when I plugged each wire into the cap. 1342 clockwise.

Mike, I didn't try any starting fluid of any kind.

Eugene, I removed the valve cover and checked the clearance according to the book, number 1 on TDC and then number 4 TDC. number 4 and 6 valves were at .012 and I adjusted them to .015 cold, like the book said. The rest were dead on at .015

Thu Sep 13, 2007 7:43 pm

Of course you can't do it with the manifold off but the old unlit propane tourch might have shown somthing. Did you hand coke with the hose off the carb as a shade tree way to check for vacume? When I see the circle on the palm of my hand and some gas I get a clue or two.
Bill

Thu Sep 13, 2007 8:00 pm

Rick,

Let us know how it goes once the new gaskets are on.

Thu Sep 13, 2007 8:12 pm

Rick, in all of this I did not see nay mention of you checking for a good spark, unless I overlooked it. Have you checked for spark form the coil? and if it is good, form the plugs at the right time?

Thu Sep 13, 2007 8:16 pm

John - in step 10 he says he has bright blue spark at all plugs.
This is getting interesting!

Thu Sep 13, 2007 8:16 pm

I hesitated to add to this because I have seen how capable you are Rick. I saw the reasoned step by step you did and the known good parts you swapped with and it even boosted my thoughts of you higher than they were to start with.