halfacre Posted July 22, 2008 Posted July 22, 2008 Smoke and oil are coming out of places on my 13hp briggs that aren't supposed to emit smoke & oil, so it seems I need to replace the head gasket at a minimum. If I'm not wrong about that, can you rate the difficulty of this task for an novice mechanic like me? Ot should I just sell this thing and move on?
D-17_Dave Posted July 22, 2008 Posted July 22, 2008 Replacing the head gasket on an L-head engine is very simple. To fully understand what is involved in such a task if your less than experianced I would suggest obtaining a copy of the Brigg's repair manual. This FULLY covers about anything you might need to know about these engines and will make short work in helping you out.
halfacre Posted July 22, 2008 Author Posted July 22, 2008 Thanks for the rapid response. I'll look for a manual and let you know how it goes. Looks like the gasket kits are about $27.
ZippoVarga Posted July 23, 2008 Posted July 23, 2008 Gasket "kit"?? If the only thing that's leaking is the head gasket then you can get that one gasket for about 8 bucks. Dave gives good advice. Get the manual. It will help you beyond your wildest imagination. Good luck and welcome to the club. It's the best 10 bucks you'll ever spend.
halfacre Posted September 8, 2008 Author Posted September 8, 2008 I did find just a gasket for $6 and performed the surgery yesterday. The old gasket was still in one piece, so maybe the head just needed to be tightened? Anyway, I was able to scrape quite a bit of carbon off of the head and the chamber, put the new gasket in and put it all back together without much trouble. However it is still running rough & backfiring?
Willy Posted September 8, 2008 Posted September 8, 2008 You may have gotten some of the carbon under the valves, if that's the case it should clear up after running it for awhile at least 1/2 throttle or more. If after a time it still runs rough you may have other issues. Don't let these thing intimidate you they can all be fixed with a minimum of of knowledge and a lot of money.:D They realy do get simpler after you work on them a while. Good luck and welcome to the gang.
CDeHeer Posted September 8, 2008 Posted September 8, 2008 If you've done a head gasket you might as well move on to a valve job. Not much further to dig and only a couple "specialty" tools required. Valve spring compressor = $25.00 Valve rotator = $4.00 (Harbor Freight) Lapping Coumpound = $7.00 Feeler Guage = $10.00 Above mentioned manual will guide you right. After you have this one purring again you'll have the tools to fix the next one or help a neighbor out with his. Good Luck, Don't sell yet!
DMedal Posted September 9, 2008 Posted September 9, 2008 Wrench therapy is good for the soul, not so with ordering unneeded parts, so let's consider a bit of diagnosis next. You say: quote:Smoke and oil are coming out of places on my 13hp briggs that aren't supposed to emit smoke & oil specifically where and under what conditions? how about performance, except for the wayward oil, does it run ok? Keep at it and it will yield its secrets and run good again. -Don
halfacre Posted September 10, 2008 Author Posted September 10, 2008 Thanks for the input & moral support. I did expect it to even out after letting it run for awhile but this approach lacked popular support from the key wife-&-toddler demographic. Now it won't start (turns over but no go). Anyway, here's where I saw oil spitting out: And here's the cylinder before I scraped carbon off: And after: By the way, I've also replaced the old fuel filter and a cracked breather tube. The PO used to get it to start by opening up the main carb jet all the way, but even this dubious method isn't working now.
DMedal Posted September 10, 2008 Posted September 10, 2008 That is, indeed a pretty ugly head. Looks like you got it cleaned up ok. Carbon in that area would be normal if it was run rich, but oil really shouldn't be. However the products of incomplete combustion can look a lot like motor oil, so maybe there is hope. compression, spark, and fuel - if you have all three it's going to fire. The comment on the oil makes me wonder about compression. If it appears to spin over too easily then compression's a problem. Other than that, you need a compression tester to assess compression. So let's let that go for the moment and come back later. It looks to me like getting adequate gas in there hasn't been a problem in the past. Are you delivering gas now? If so, you should have a definate raw gas smell from the exhaust. (unless it is firing rough but won't keep running). If anything you have too much. So go through the initial carb setup, which is (if memory serves) gentle all the way in on the main jet and then back out 1 1/2 turns. Check spark at this time too. A spark tester is the best tool here, but most of us fake it by removing the plug, holding the side of the plug solidly on the block with insulated pliers and cable hooked up. You should see a spark across the gap. after checking carb and spark, and both passing, attempt start again. If indeed you need lots of choke just to keep it running, or need to open the main jet all the way up, you probably need a carb overhaul as there's probably old crud inside. But first let's see how your check of fuel and spark testing goes. -Don
halfacre Posted October 25, 2008 Author Posted October 25, 2008 quote:compression, spark, and fuel - if you have all three it's going to fire. Great words of wisdom, thanks. Unfotunately it seems to be a compression leak. When the starter is turning it over, I put my hand over the head and I can feel air blowing out at a spot on top and another spot on the side. Maybe it's warped?
halfacre Posted June 23, 2009 Author Posted June 23, 2009 Just to follow up on this. I ended up hiring a pro to fix it, and he told me the points needed work and carb was dirty. Now it starts easy and purrs nicely.
Storm7012 Posted June 23, 2009 Posted June 23, 2009 Did you lap the head when it was off? I had to change the head gasket on my 7016 and a friend told me to be sure and do that.
Dark Posted June 24, 2009 Posted June 24, 2009 compression testers are OK but only tell half of the story a leak down test would be more accurate.
nateb17010 Posted June 24, 2009 Posted June 24, 2009 Storm7012: "Did you lap the head when it was off?" how do you do that? use a big sheet of sand paper and tape it to a sheet of glass? go in a figure 8 nice and slow until the mating surface shines? you left it a little confusing. halfacre: how is the oil comsumption? 1) 1 qt to a gallon of gas. 2) never checked my oil. 3) 1/2 qt to gallon of gas. by the look of how wet the deck of your engine is , it"s in need of rings, but if you keep an eye on your oil and even run some additives with your oil. right now you say your engine runs good. cool good to hear. dose it smoke a lot or just under a load?
Storm7012 Posted June 24, 2009 Posted June 24, 2009 Thats how I did it, just the way you said. I put just a little bit of oil on the sand paper and go slow till its all smooth.
halfacre Posted July 1, 2009 Author Posted July 1, 2009 quote:Did you lap the head when it was off? No I didn't, but thanks for the tip. I asked if the head was warped at all, and was told no it's fine. quote:how is the oil consumption? I've never measured it in relation to gas consumption. I check it before each use, and it always seems to need a little. However I don't see any smoke. quote:its in need of rings What's that? quote:run some additives with your oil Can you recommend an additive? I have some "Marvel" stuff.
MrSteele Posted July 2, 2009 Posted July 2, 2009 Your pics showed the carbon before and after. The "after" pic looks like you did not completely clean the gasket mating surface on the block. If you also did not clean it on the head, you might still have a compression leak there, and will never be able to tighten the head enough to make the gasket seal. It will not start now? Does it hit at all? Is everything connected as it should be?
halfacre Posted July 2, 2009 Author Posted July 2, 2009 Starts & runs fine now. Thanks for the tip on cleaning head.
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