B&S Intek V-Twin blowing blue smoke

[Rivets]

Looking at your pics I don't see evidence of a blown head gasket, but it may be under the gasket which is still on in pic #2. Definite evidence of oil ingestion. Easily clean with a wire brush and a good cleaner. You will have to pull the valves and clean then. May have to regrind the seats and valve faces. Send pics after they are cleaned, so we can see condition. I don't want to scare you, but I would be pulling the other side and take a look in that cylinder. This is starting to look like a total rebuild, but let's do some checking first. At this point I ask my customers, how much do you want to spend? I know that you will be doing most of the work, but can you lay up the unit for two weeks or more due to your schedule and getting answers to your questions. I could easily see $150 in parts alone. I think I can talk you through this, you may have to outsource a couple of steps. Let us know what your thinking.

 

[RichardHiggins]

First off, thank you for your detailed responses, I really appreciate your help.

What are my thoughts? Well, I can say I was hoping to get out of this for less than $100. If I am going to spend $150 or more, I might start thinking about a used walk behind. Time does matter a little because the grass is gonna grow, but the money matters more. Work has been pretty slow for the last 8 months, and the budget is kinda tight.

As for pulling the other head, I noticed right away when I pulled the old plugs that the left plug looked like it was good for at least another season. Pulling that head would mean 2 more gaskets, which inches me that much closer to the $150 mark.

I take it you're thinking that I need to hone the cylinder, correct? The crosshatch concept in the repair manual makes this sound like some sort of CNC job. Is it something that can be done with a cordless drill?

Lately I've started to wonder if this was all caused by the Valve Seal rather than the Head Gasket. The deposits show an interesting pattern around one of the valves.

I would love to clean this up, find and repair the fault, and put it back together. But you're the expert and can tell me what that solution would utimately mean for the life of the tractor.


-Richard

 

[Rivets]

You could try to do one side now, hope that it makes it through the season. As long as you have one head off and clean it good. Clean the cylinder with a rag and cleaner, NO SCRAPING IN THE CYLINDER. carefully scrap and clean the top of the piston when you have it all the way up. After you have everything clean we'll look to the next step.

 

[RichardHiggins]

Well, I borrowed a microscopic inspection camera from work today, and stuck it in the left spark plug hole. You were right, I should pull the other head. There was definitely gunk on top of that piston.

Interesting development today. My boss approched me and offered a little overtime. Now my situation is inverted. I'll have more money to tackle this, but less time!

Thursday morning I will head out to get the gaskets, some feeler guages for the rocker adjustment, and some cleaner. Thursday afternoon I should be able to start digging in to this. Thursday and Friday is all I've got this week, back to work on Saturday.

Any brand recommendations on the cleaner? I'm kind of a health nut, so the least toxic option would be best.

You mentioned having the piston "all the way up." Do I accomplish that by turning the Flywheel?

Do you think I should get a new Valve Seal? And if so, is the special tool really necessary to install that?

Thanks,
Richard

 

[Rivets]

Cleaners, don't have any recommendatios, I use the cheapest carb cleaner I can find. Don't know of any that are good and Eco-friendly.
Yes, turn the flywheel until piston is level with top of cylinder.
Yes, get new valve seals, no special tools needed.
Send pics of the valves and heads after cleaned, will tell you how tp proceed after viewing.

 

[RichardHiggins]

So, I called the local shop about the parts. We got to talking, and in the end he said don't bother. As a previous poster commented, the dirt that got sucked into the engine pretty much destroyed it. So I give.

Went to Lowes yesterday and bought a Husqvarna self-propelled walk behind mower. Takes a while to mow an acre that way, put I'm getting good exercise.

It has a Honda engine. My wife is adamant that we will never buy a Briggs & Stratton engine again. We even made sure the bottle of oil we picked up was a non Briggs & Stratton brand.

The rider will go into deep storage until I can afford a new engine.

Thanks all for the help anyway!

 

[Rivets]

Richard, you are really going to get mad and upset with me for saying this. (And so will a few other people on this forum). What you are blaming on B&S is not their fault. I would really like to see your air filter and maintenance records. I have seen this situation too many times before, lack of consumer maintenance, blame it on the manufacturer. This problem did not happen overnight. That tube should have been seen by whom ever was doing the periodic service. I'll bet the tube was on there when you bought it. Did B&S take it off after it was purchased? You never said how old the unit was. Who has been doing the yearly service, could they be the problem? I have been teaching engine repair and repairing engines for 35+ years and yes manufactures make mistakes. Have you ever heard of recalls? This was not a manufacturers mistake,(based on what you have posted) but the consumers problem for not following maintainence instructions. I have fought with the manufactures when I see problems which are not the fault of the consumer, but in this case I am going to side with B&S, this is your fault.

 

[WISCOPROUD]

your Honda will do the same thing as your B&S if you suck dirt into it. I back Rivets as a dealer of both Honda and B&S. Not Briggs fault but your own. VERY important to keep dirt out of motor. :laughing:

 

[PJ]

Hello all,

New member here looking for some advice on my Craftsman mower. It recently started smoking real bad, and using up oil at an alarming rate. I know you're going to hate me for this, but I kept adding oil and kept mowing. Hey, the grass was REAL long! I knew I had a problem, but figured I'd address it once the forest was cleared. It took two refills to finish my 1 acre lot. After a while it sounded like it was running on one cylinder. I pulled the plugs and sure enough, the right side plug was gunked up real bad. I put in new plugs and some stop leak and kept going. This was meant as just a band aid until I could finish the lawn. Thing was, stop leak didn't help.

I purchased a B&S Repair Manual yesterday. The guy at the store said he suspected the Breather Tube. Once I figured out what a Breather Tube was, I found that it had come loose from the Air Horn! I cleaned everything up real good and reconnected that tube. Fresh oil, new filter, and gave it a whirl. No luck, still blue smoke real heavy.

So, given my limited knowledge here's my thoughts. I am suspecting either a blown head gasket or bad rings. My problem now is that the book calls for a Flywheel Holder at $65 and a Flywheel Puller at $15. I am afraid of investing in these tools only to find I can't fix it. Quite frankly, funds are limited.

So here are the main questions:
1 - Is there another way to get the flywheel off safely without those tools, or at least can I make my own Flywheel Holder?
2 - What are your thoughts as to what the problem could be?

Important Details
Mower:
Craftsman DYS4500
Briggs and Stratton Intek V-Twin 24HP OHV, Model 445677-0827-e1

Me:
Electronics Technician
Pretty handy with tools
Know little to nothing about motors. However, changed my own timing belt, drive belts, and alternator on my Honda Civic two weeks ago. (Love those Hanes manuals!)

Hi
you can remove without puller but damageing crank and casing is very good. Try and obtain a puller general purpose from second hand dealer or on the forum will be worth it. i agree it is not a tool you would use every day. Do you have a repair manual?
Good luck sounds like a engine overhaul coming up.

PJ

 

[OrtisEvans]

Your issue may be long resolved by now, but just in case... I know that on some OHV engines, valve stem seals are critical. If they are bad, oil drips down the valve stem into the cylinder.

I had "blue smoke syndrome" on one engine that developed overnight. I added some "Sea Foam" (brand of flush) to the oil and it 20 minutes, it cleard. I suspect the problem was clogged oil retun passages in the head, allowing oil to collect, drip down the valve stems, ... However, you have pulled the head, and would know if that were the issue.

I wonder if a crankcase pressure-powered fuel pump ( I have one on a generator) can fail in a way that lets oil mix with the gas. I had one fail once, but I had a crankcase full of gas rather than oil in the carburetor.

Good Luck
Ortis