OK guys here goes. I just did a full rebuild kit on the carb. It included a new main jet. Well put it back together and it wont start. When I prime it there is air blowing out and sucking into the weep hole.Fuel flows outta the feed line, opened the bowl nut fuel comes out. Wont run on ether right now had it running on ether before the rebuild. Spark is good.

After a while of messing with it FUEL was squirting out of the weep hole when I pushed the primer bulb. (This primer bulb is mounted on the side of the engine not on the carb itself)

ANY HELP WOULD BE SOO GREAT! I spent 2 COLD hours trying to get it to start today!!

Don

 

He/she said it has good spark. Well, if it indeed has good blue spark and it won't start on a good shot of Ether, there's something else wrong. After trying to start it is the spark plug wet? Does the oil spell like gas?

 

Yeah good spark nice and blue. It would run before with ether I dont have a way to test for compression. Plug was dry earlier hadn't looked at it when I gave up trying. Oil and gas are still separate. Pretty sure its a carb thing. The sucking air and then squirting gas thing is not right.

 

When you re-built the carb, did you soak it in a bath then rinse with a spray cleaner & dry with compressed air?? Did you replace the needle seat & adjust the float?? It still sounds blocked somewhere??? This carb doesn't have removable jets, does it? Roger

 

Rog, Didnt soak it, did carb cleaner and soak main jet (but a new one came with the rebuild kit) then dried with compressed air.

Removable jets? The bottom one is, there is another adjustment screw is that what your talking about? Also above the main jet(in the bowl nut) there is another "passage" looks like the bowl nut kinda goes over it, hard to explain maybe I'll get some pictures.

THANKS FOR THE HELP!

 

What are the engine numbers? What carb kit did you use?

 

I must've been half asleep last night when I read these threads... (this is the second one where I missed obvious info). I see that it has good spark...sorry to ask what you've already stated.

I know you haven't got a way to test compression, but do you feel the resistance of compression while you slowly crank the engine? If the plug is dry and there is good spark, and it has compression, then it should respond to the ether.

It also sounds like there may still be a carb issue as you suspected.

 

Try not to laugh, but I forgot to mention on my last post, You do have the tools to check compression. With the ignition off, remove the spark plug & put you're thumb over the hole with light pressure. Crank the engine as if trying to start it. Does it try to blow you're thumb off the plug hole??? Not a very sientific test, but it will at least tell us if the piston is moving up & down. Let us know the results, Roger

 

Don,

What was the symptoms of this engine before you rebuilt the carb/ What made you think the carb needed rebuilt ?

 

Bowl has not got any gas in it. Passage above the main jet is clear, new fuel lines to tank and primer bulb. Fuel will cut off when I manually push the float up. I am really STUMPED ON THIS!!! DAMMIT!!

smallengineguy: HS50 67174C G129B Carb Kit #31840

cheese: I do feel a little resistance, plug was dry (Checked again today when I re-re-re-removed the carb also rechecked spark and really opened up the tester prolly .45 or so GOOD.

Rog: I could see the valve move up and down but I will have to try the thumb on the hole trick some time maybe Sunday.

31YTech: Symptoms were same as now primer not doing anything and engine not starting even on ether. Took carb off and did a quick spray out reinstalled THEN it would start with ether and the primer bulb would FLOOD the carb. Since then I have done the rebuild kit and really cleaned the carb (Also replaced the welch plugs today) and its back to primer sucking air and ether not starting it.

I really appreciate all your all's help on this. The 2 stroke I got is running MINT and clearing the driveway cept for the very end which is why I want this one to get working.

THANKS ALL!!!! Please keep the ideas coming. If I have to I'll get a compression tester from AutoZone (I work there part time LOL) Should have already done this huh!!

 

sounds like the fuel inlet to the emerson tubes & main jet is,is still glogged up.this hole on most tecunseh engines is real tiny and is located between the threads of the bowl nut.Just run a small wire such as a bread tie or a torch cleaning drill through it.Also the hole leading from this hole to the main jet.And if the bowl is still leaking fuel from the overflow hole as described in post #1 (the the weep hole,as you called it) Then something inside the carb is still clogged also.Soak the carb. for 30-40 minutes in good carb acid bath.removing all rubber and plastic parts B 4 hand.
And also real important,replace the fuel in the tank because 80% of the time when the carb is clogged and rebuilt and the fuel isn't replaced with clean fuel,it will happen again real soon.

 

Yeah, That would be a good idea. If a engine will not pop/spit or sputter on ether having good spark that could lead to non-seating valves and or worn valve guides.

 

Main jet is new. carb wont even respond to ether. Gas isnt just coming out of the overflow it was only coming out when I push the primer bulb.

 

I work again Monday so I'll try to get one. I will try the thumb thing today sometime though. What am I looking for 90psi you say?

 

OK, the 31840 kit came with both a main jet and an idle adjustment screw, You said you replaced main jet did you replace idle adustment also. Main jet should be tighted to seat and the backed out 1 1/2 turns. Idle adjustment seated and back out one turn. I agree with fresh gas from pump not can. Very important but if not starting on either we can look beyond that I think. Put in a new spark plu J19LM gapped at .030, with fresh gas and carb adjusted to above specs and let us know.

And yes you are looking for 90ish on compression but engines will start with as low as 60

 

I have a question dcjredline.Maybe I missed it but,you said that your engine woulden't even hit on ether.Where did you put the ether in at,the spark plug hole or in the carb where the air filter would fit,if your engine would have one?

The reason I ask is if you put it in spark plug hole,Then you would expext it to pop anyway.but if you put it in at the carb.,the eather might not be getting to the cylinder to cause the engine to pop.

 

Did replace the other screw too. Fresh gas is on the list for tomorrow and so is the compression tester from AZ. THANKS.

I was spraying the ether into the carb but decided I would do it into the plug hole once just to see and it would actually sputter more than before. When I say sputter more I mean sputter ONCE or TWICE nothing major!! Is that still a good ($ wise) sign?

 

Ok all its official. Even though its 13F outside (About 22F in the garage) I did the compression test tonight since I just got back from work. I think its not good and most here were right!! I dont know why but.....


The compression while being pull "started" was NO HIGHER than 40psi. I think thats ROUNDING UP too. Gauge has 30 60 90 120 on it so its not really meant for lawn mowers I guess but defiantly was right over the 30 marks.

What are the next steps? Basically. Rebuild? Never did this before to any engine, but I am looking forward to the challenge.


DON

 

When you did the compression test did you give 4 good strong pulls? You need to go through all 4 cycles.

A "rebuild may be a bit premature. Low compression could be caused by a blown head gasket. $5.00 part, could be valves not seating correctly or a piece of carbon holding the exhaust valve up a bit. Lastly could be your rings are failing. If you have a local shop that can do a leakdown test for you, you can find the problem pretty quickly and move forward accordingly. Sometimes just lapping the valves and a new head gasket will do the trick.

 

Ohhh!! LOL! I did try to pull it 2x once and the comp went to almost 60. LOL! I didnt know that. Guess I'll try it tomorrow morning and let ya know when I get to "other" work.

THANKS for bearing with me I'm a noob at this kind of stuff.

A new gasket or valve lapping would be NICE! Guess I'll see when I get into it. I will get you all some pics during the process too so maybe you (With more experience) will see something I dont!!

 

OK did the test again with 4 strong pulls, didnt make it to 60psi. Still a problem?

 

It doesn't look too good, For a few bux (head and valve cover gaskets) I would suggest popping the head and visually check the valves (seats and faces), With the valve up (open) grab the head of them and see if they wiggle in the guide.

The exhaust guide is the most common one for excessive wear.

 

TANKS, it'll have to be a weekend project. I will check back in on Sunday and update. Thanks again.

Don

 

OK, well both valves open and close just fine. I cleaned the tops and sides of them both this weekend. While I had the top of the engine off I took the muffler off and it was WIDE OPEN right at the block (Rusted). Could this cause the engine not to start? The passages to the intake and exhaust valves are clear (I blew air through both of them and sprayed some carb cleaner in them.

31YTech: I didnt wiggle them (FORGOT) but I will tonight and report back tomorrow.

 

The exhaust problem doesn't sound like something that should be keeping it from starting if I understand your description correctly.

The "wiggle test" will tell more of the condition...also, look at the cylinder...are there any gouges or heavy scratches in it?

 

Cylinder is CLEAN AS A WHISTLE top of the piston and the cylinder walls.(How thats clean I dont know) and I FORGOT to wiggle the valves sorry. I'll try tonight.

As far as the muffler goes if you understood that the muffler might as well have been completely removed then you got it right. Would it start without a muffler on at all?

 

Sure, Most any engine will but you don't want to run one for a long period of time without because it could cause the valve face/seat to burn/crack or pit.

 

DARN sorry it took me so long. I actually checked the valves the other day but everytime I am on the puter I forget to update you all for some more guidance...

The valves are nice and tight. They turn but dont shake or wiggle. Whats next?I am thinking about putting it back together and see if it will work now since I cleaned the valve faces off. Maybe there is compression now!! What would you all suggest?

 

If you're sure the carb is clean & the valves are O.K, Try a teaspoon of oil in the cylinder. All the ether & flooding may have washed the rings down. The oil will seal the rings to the cylinder bore & you may have more compression. Just a guess, Good luck, Roger

 

what about cratches, scrape marks, and/or grooves in the cylinder?

 

One of the Techs in my shop had a simular occurance on an HS50. Everything checked out and while it was torn down I just happen to go by his bench and stop to answer a question that he had. Looking at the unit I noticed that the flywheel magnets were not near where the coil is located. He pulled the flywheel and found a sheared flywheel key. With the head off you should be getting spark near the top of the piston stroke. If not look at the flywheel key. You need three things for the engine to run, fuel, compression and spark and they have to occur at the same time.

 

Thank you all, I will do those 2 things next. I started to think to myself that there wasn't any oil in the damn thing but didnt think about putting it in on top of the piston. THANKS. So keep the head off and have the spark tester on the wire to see WHEN I get spark.That'll be easy


Cheese: The walls are not scratched at all, inside of the cylinder looks really clean.

 

dcjredline, did you ever soak the carb in a bath type cleaner as was suggested early on??? I still have a feeling you have a blockage & no spray cleaner can get into the passages of a carb & properly clean them. Also make sure you have fresh, clean REGULAR grade fuel in the tank & carb. These carbs & fuel can do strange things to fool you. Let us know,, Roger

 

I didnt I dont have the cleaner. I will try it though it wont hurt. Clean gas I will have to work on too.

 

Unless I missed it somewhere, you didn't check your valve clearances. Did you? They both need to be set at .008". I'll bet your exhaust valve clearance is nill.

 

Puey is right, & the time to check the valve clearance is when the carb is off as the cover is kinda tucked under the carb...Good luck, Let know what you find!!! Roger

 

I did not. But I will need a little guidance on where to measure the .008 at. Sorry I have never done it before. I have the carb and the muffler off at the moment.

 

Remove the valve cover (it's the same piece that the rubber breather hose is connected to) and place the engine at top dead center, and measure between the valve stem and the lifter.