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    26HP twin "V" overhead valve Briggs and stratton nightmare!

    Asked Sep 10, 2007, 04:32 AM 10 Answers
    Ok, this is going to be a long post/question, but necessary for everybody to get the whole picture. I purchased 3 (non working) identical 26HP briggs engines. The idea was to get them running, and sell 2 of them, getting the 3rd one free.

    They are intek 446777 overhead valve engines.

    I started with the first, taking the bottom end apart to check crank,connecting rods, timing etc. Looked great inside, like new. Then checked the valves. Exhaust valve gap on both sides was 0.030 or larger. It was a carboned up mess. I pulled the heads, cleaned very well, reassembled and set all valves to 0.005. Attached fuel line, jumber cables to the fuel solonoid, touched the starter... vvvvvvvvrrrrrrroooooooooommmmmmm!

    Just like new! Sold it with-in a week! I love it when a plan comes together!

    Now the second engine. Same process. Found same problem. Fixed same way... Started her up... and hhhhmmm

    Ran very raged. Then I noticed the exhaust on the side opposite the fuel pump was throwing extremely hot gas. Way hotter than normal. I shut it down. Figured there was still a problem with the exhause vave. Reset it, and checked other side. It seemed OK. It was quittin' time so the next day went back at it. Now, I couldn't get it to even run. While cranking, it was firing almost as thought it was running, but the second I stopped turning the starter, it quit.

    I read somewhere on the net to put a teaspoon of fuel in right in the cylinder, put the plug back in and see if it fires. When I did that, as I turned it over, I saw gas come out somewhere. Ah... ha! I thought. The head gasket is blown and leaking. I pulled the head back off and looked VERY closely at the gasket and head, and machined surface the head mounts on. Everything looks perfect! I put the head back on, retightened and tried it again. This time, no gas leaking and it DID fire. HHhhmmmmm Ok, so maybe a carb. Problem. I pulled the carb. Totally disassembled, cleaned, checked all gaskets, (looked like new). Put it back together.

    Now, it won't even fire. The starter turnes and turnes and turns... not so much as even a puff!

    When I turn the flywheel backwards, I get a huge amount of resistance which if I understand correctly means compression is fine.

    Can a head gasket be blown and not show it? Oh, one other thing that will make you mechanics cringe... I don't have a torch wrench. I was very carful to retighten the heads as evenly as humanly possible and very tight. Could this be the problem? Where would you turn next?

    Oh, yeah, one other thing. I grabbed a plug wire and turned it over... GREAT SPARK on both sides. Made my teeth chatter! Lol


    HELP!

    Thanks in advance... Tim

    Last edited by hover_rat; Sep 10, 2007 at 04:43 AM.
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    hover_rat's Avatar
    hover_rat Posts: 8, Reputation: 2
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    #2

    Sep 10, 2007, 02:35 PM
    Quote Originally Posted by hover_rat
    Ok, this is going to be a long post/question, but necessary for everybody to get the whole picture. I purchased 3 (non working) identical 26HP briggs engines. The idea was to get them running, and sell 2 of them, getting the 3rd one free.

    They are intek 446777 overhead valve engines.

    I started with the first, taking the bottom end appart to check crank,connecting rods, timing etc. Looked great inside, like new. Then checked the valves. Exhaust valve gap on both sides was 0.030 or larger. It was a carboned up mess. I pulled the heads, cleaned very well, reassembled and set all valves to 0.005. Attached fuel line, jumber cables to the fuel solonoid, touched the starter.........vvvvvvvvrrrrrrroooooooooommmmmmm!

    Just like new! Sold it with-in a week! I love it when a plan comes together!

    Now the second engine. Same process. Found exact same problem. Fixed exact same way......... Started her up.....and hhhhmmm

    Ran very raged. Then I noticed the exhaust on the side oposite the fuel pump was throwing extremely hot gas. Way hotter than normal. I shut it down. Figured there was still a problem with the exhause vave. Reset it, and checked other side. It seemed ok. It was quittin' time so the next day went back at it. Now, I couldn't get it to even run. While cranking, it was firing almost as thought it was running, but the second I stopped turning the starter, it quit.

    I read somewhere on the net to put a teaspoon of fuel in right in the cylinder, put the plug back in and see if it fires. When I did that, as I turned it over, I saw gas come out somewhere. Ah....ha! I thought. The head gasket is blown and leaking. I pulled the head back off and looked VERY closely at the gasket and head, and machined surface the head mounts on. Everything looks perfect! I put the head back on, retightened and tried it again. This time, no gas leaking and it DID fire. HHhhmmmmm Ok, so maybe a carb. problem. I pulled the carb. totally disassembled, cleaned, checked all gaskets, (looked like new). Put it back together.

    Now, it won't even fire. The starter turnes and turnes and turns....not so much as even a puff!

    When I turn the flywheel backwards, I get a huge amount of resistance which if I understand correctly means compression is fine.

    Can a head gasket be blown and not show it? Oh, one other thing that will make you mechanics cringe....I don't have a torch wrench. I was very carful to retighten the heads as evenly as humanly possible and very tight. Could this be the problem? Where would you turn next?

    Oh, yeah, one other thing. I grabbed a plug wire and turned it over.......GREAT SPARK on both sides. Made my teeth chatter! lol


    HELP!

    Thanks in advance........ Tim
    Ok... update... DUH!
    I found one small problem. I have a rigged gas tank for testing. The fuel hose got pinched as I worked on it late last night. That is why it wouldn't fire at all the last try. The good news is I am back basically where I started (it fires). The bad news is it still won't start and run. I checked every other connection. I have two separate mufflers attached like duel exhaust. The first engine ran fine on these same mufflers. When I say it is firing, it is like this. When I am cranking it it goes: Pop, pop, puff, puff, puff, pop, puff, pop, pop, puff. It just won't start! Both sides are firing intermittently because both mufflers are getting hot. Now what... anybody? Anybody?

    Tim
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    MOWERMAN2468's Avatar
    MOWERMAN2468 Posts: 3,214, Reputation: 243
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    #3

    Sep 10, 2007, 06:38 PM
    Man, let me see if I can pick out some parts to help you on. First off , the fuel not being able to get to the carb will not keep it from firing at the spark plugs(I guess is what you meant). Another, I am not sure you set the valves correctly, I am thinking you may have tried to set the valves without ever moving the flywheel in between the setting of the two cylinders. And if you are getting fuel out the exhaust I would say that you are not getting fire in that cylinder. And then I am leaning toward the flywheel key being sheared. If the valves are set correctly and the flywheel key is sheared, then it will spit, blow, pop, and puff. Because as the piston comes up to compress the air and fuel mixture for combustion from the spark plug's spark, it is not in time on the flywheel and coil, therefore, you may be sparking on the intake, exhaust,or power stroke. Check flywheel key.
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    hover_rat's Avatar
    hover_rat Posts: 8, Reputation: 2
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    #4

    Sep 11, 2007, 03:18 AM
    "the fuel not being able to get to the carb will not keep it from firing at the spark plugs (i guess is what you meant). "

    Well, I didn't mean just spark, I meant when I put gas in the cylinder, it fired as in "popped". I DID rotate the flywheel before setting the valves on the other side though. One more thing that bothers me is this: There seems to be "play" in the rocker arm. There are no caps on the end of the valve stem on this type engine and it just seems, even though the center screw is tight, the rocker arm has enough play to make setting the clearence exactly, really, really difficult. Just when you get it set right, if you "wiggle" the rocker arm, the setting is off. Does this seem normal?

    While cranking, both cylinders are firing because both mufflers get warm. But what you are saying about timing makes sense. That is what it seems like to me. I even took the bottom end apart again at one point to check the timing marks. They are lined up. So, maybe you are right about the flywheel key. I can check it by just pulling the nut off the top of the flywheel and looking at it without pulling the flywheel, right?

    It sure seems to me it is either the valve settings or the timing. I will check the key after work tonight, and reset the valves again for about the 10th time.

    Thanks for the help, and keep the ideas coming! I need all the help I can get!

    Tim
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    hover_rat's Avatar
    hover_rat Posts: 8, Reputation: 2
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    #5

    Sep 11, 2007, 02:04 PM
    MOWERMAN2468 YOU ARE BRILLIANT! THAT WAS IT! Sheared flywheel pin! It sucks, but I have to go away for a few hours. I checked the nut and bolt shelf, and sure enough, I have a piece of key stock just the right size too! As soon as I get home, I will cut a piece and get it in. That motor should be running by 9:00 tonight! If you were mowerlady I would give you a big kiss on the lips!

    Tim
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    hover_rat's Avatar
    hover_rat Posts: 8, Reputation: 2
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    #6

    Sep 11, 2007, 04:48 PM
    Here's to you Mr. Mowerman... you were the only one that took the time to answer... and you hit it right on the head. New key is installed, and she purrrrrrrrrsssssss like a kitten!

    The Budweiser is on me buddy!

    Tim
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    MOWERMAN2468's Avatar
    MOWERMAN2468 Posts: 3,214, Reputation: 243
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    #7

    Sep 12, 2007, 09:54 AM
    Another simple fix, when it seemed as though you were going to go crazy. Always see your cup 1/2 full instead of 1/2 empty. Talk to you later, good job on your part for sticking with it and getting it back going.
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    hover_rat's Avatar
    hover_rat Posts: 8, Reputation: 2
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    #8

    Sep 12, 2007, 10:34 AM
    Good advise! Sometimes it is just such a simple problem. Right there in front of you. It is easy to get frustrated and let your mind start racing to all the possiblilities it COULD be instead of just slowing down and taking it a step at a time. It is so rewarding to have fixed it. (To your credit of course) but what a great learning experience!

    Thanks again, Tim
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    MOWERMAN2468's Avatar
    MOWERMAN2468 Posts: 3,214, Reputation: 243
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    #9

    Sep 12, 2007, 06:03 PM
    Quote Originally Posted by hover_rat
    Good advise! Sometimes it is just such a simple problem. Right there in front of you. It is easy to get frustrated and let your mind start racing to all the possiblilities it COULD be instead of just slowing down and taking it a step at a time. It is so rewarding to have fixed it. (To your credit of course) but what a great learning experience!

    Thanks again, Tim
    You did learn a great deal from this experience. And experience is the best teacher there is. You done well.
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    Dannyo's Avatar
    Dannyo Posts: 1, Reputation: 1
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    #10

    Sep 15, 2010, 03:15 PM
    I had the same problem. I filled the fuel bulb and reassembled. Not the easiest thing to do without spilling fuel. It worked great for me! It seemed to prime the carb I think.? Dano
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