Issue with Briggs 8hp

[ronspol]

Hello All,
I have an 8 hp Briggs on a generator, model is 195432, type is 0779 01. The original motor was getting loud (like a metallic type knock) so I located a direct replacement Briggs short block. I now cannot get this motor to start, fuel never enters the combustion chamber (dry spark plug). I have tried pouring some fuel in the spark plug hole, and spraying carb cleaner into the carb air inlet, won't even try and pop. I have good spark, its a new coil and plug. I have fuel in the bowl, and have double checked that the float sits level when upside down. When I remove the air filter and spin the recoil, I can see the fuel charge blowing out the carb air horn. I have checked that both valves are closed at TDC, and valve clearance cold is 0.006 intake and 0.010" exhaust, right where Briggs says it should be. Any suggestions? I'm wondering if the "Easy Spin" is functioning properly, but I can't find a description of it in the Briggs shop manual. Thanks for the space!!

[bgsengine]

Hello All,
I have an 8 hp Briggs on a generator, model is 195432, type is 0779 01. The original motor was getting loud (like a metallic type knock) so I located a direct replacement Briggs short block. I now cannot get this motor to start, fuel never enters the combustion chamber (dry spark plug). I have tried pouring some fuel in the spark plug hole, and spraying carb cleaner into the carb air inlet, won't even try and pop. I have good spark, its a new coil and plug. I have fuel in the bowl, and have double checked that the float sits level when upside down. When I remove the air filter and spin the recoil, I can see the fuel charge blowing out the carb air horn. I have checked that both valves are closed at TDC, and valve clearance cold is 0.006 intake and 0.010" exhaust, right where Briggs says it should be. Any suggestions? I'm wondering if the "Easy Spin" is functioning properly, but I can't find a description of it in the Briggs shop manual. Thanks for the space!!

1) check compression (Got the head bolts in the right holes, not bottomed out, head gasket not blown?)
2) try a new Spark Plug
3) Pull flywheel and check the key - if sheared make sure you torque flywheel nut properly.

Easy Spin starting is just a small lobe machined into the intake cam to lift intake valve a little bit on compression stroke to make it easier to pull the engine over. It won't cause no-start condition unless valve clearance is off, or valve timing wrong.

[ronspol]

OK, thanks for the reply. I have a new head gasket in, and the head bolts in the correct holes. I checked the head and cylinder surfaces for flatness with a steel rule and feeler gauge, its within 0.002" easy. Pulled starter clutch and flywheel, key is good and re-torqued to 75 ft lbs. With choke and throttle full open,and pulling the recoil normally I get 50 psi max. Does Briggs have a spec what the compression should be? I put 2 good squirts of oil in the spark plug hole and still get 50 psi. I do see the valves opening and closing. Maybe I should try a leakdown check and see if it leaks thru the valves? I'm stumped as this is a new short block.

[bgsengine]

I'd do the leakdown test - 50 PSI is pretty weak for any engine, but it should hit on pre-atomized fuel like spray carb cleaner. - Also might check for possible air leaks - where'd you ever find an 8 HP L-Head Short block ? Haven't seen one in years unless it was new old stock.
- Could be you got a "NOS" new old stock, or someone selling a warranty block as a short block in a short block box - did the short block have painted masking tape covering the cylinder and intake, exhaust ports? If not, it may not have been a New In Box.

[ronspol]

Well, I tried the leakdown test. Even at low pressure (30 psi), I have air in the crankcase. If I'm not mistaken, I should never have leakage into the crankcase. The story on the block is, I emailed Briggs & Stratton looking for one. They had one in stock, and it was $300. They did give me the P/N, so I ended finding one on ebay for $50 from a dealer. It did have the masking tape on across the cylinder top. Not sure what to do now, it seems to leak past the rings?

Edit: I don't think I had TDC, I believe if one valve is even slightly open it can leak down into the crankcase (valve in block). Will try again....

[bgsengine]

They did give me the P/N, so I ended finding one on ebay for $50 from a dealer. It did have the masking tape on across the cylinder top.

That is likely your problem - Unscrupulous dealer could easily put masking tape back on a clean block (or a warrantied short block) and turn it around and sell it to someone like you. I had that happen to me once a long time ago before I became a Briggs dealer. (and the shop that sold me the block is LONG since out of business - its been over 20 years now.) - They'd done a short block and then found stuck rings , warranted it (I assume since I got it for so cheap) and then after warranty got paid, they are supposed to destroy and dispose of the old part, but likely just re-taped it , put it back in the box and sold it to the first poor slob that came along that wasn't a regular customer (me) and then refused to do any warranty on it claiming that *I* had voided warranty by taking it apart to see why it had no compression.

If it is a new short block with Briggs warranty and sold by an authorized dealer, it'll be covered by warranty *IF* the failure is due to material defect - It could have been in storage on the dealer shelf for years and the rings rusted or corroded to piston (stuck rings), as mentioned, and may not be covered by any warranty.

There will be *some* leakage past the rings even on a new engine - the question is, HOW MUCH. So, you'd need a flow meter to determine the rate of leakage - a new short block should be less than 20% but there'll always be some due to ring end gaps.

Was I you, I'd have bought the one from Briggs and run like hell from someone selling a "new" short block for far, far below dealer cost.

[KE4AVB]

All I can say is that the dishonest shops far out number the honest ones...

[creia]

[quote="ronspol"] They did give me the P/N, so I ended finding one on ebay for $50 from a dealer.

I'm with Brian (bgsengine) on this. It looks like you got screwed. What is that old expression- "If it sounds too good to be true it probably is'? A legitimate NOS 8 HP for only 50 bucks?- get real!
Did the Ebay seller (dealer) make any representations in his ad about the condition of this engine other than "NOS"? Does he have a refund policy?

[ronspol]

OK. I think I may not have understood your question. I bought this short block over a year ago, just now getting to the project. The seller had many different short blocks for sale, I was the only one to bid on this older unit. It did have wide masking tape across the cylinder and intake/exhaust ports, and the tape had the same color gray paint on it as the block, as I believe Briggs used it as paint masking and just left it on? It had a number written on the tape, maybe H19 (I dont remember as I took the tape off a year ago)? Besides, my project isn't worth the $300 for a short block, I would just junk it and get a new generator. For $50 and some time (which I now have plenty of) I'll take a chance as a project.
Does Briggs spec a leakage rate? I can try and round up a calibrated flow meter and test it. Would the best approach be to just install fresh rings and clean the piston up?

[KE4AVB]

OK. I think I may not have understood your question. I bought this short block over a year ago, just now getting to the project. The seller had many different short blocks for sale, I was the only one to bid on this older unit. It did have wide masking tape across the cylinder and intake/exhaust ports, and the tape had the same color gray paint on it as the block, as I believe Briggs used it as paint masking and just left it on? It had a number written on the tape, maybe H19 (I dont remember as I took the tape off a year ago)? Besides, my project isn't worth the $300 for a short block, I would just junk it and get a new generator. For $50 and some time (which I now have plenty of) I'll take a chance as a project.
Does Briggs spec a leakage rate? I can try and round up a calibrated flow meter and test it. Would the best approach be to just install fresh rings and clean the piston up?

Check with some your local auto part stores for the tool. Many has loan a tool programs.

I think this where your problem lays. This block never had been used just sitting exposed to humidity for a very long time. Never had any of fuel lubricates that normally prevent corrosion. I think you will need to take the short block a part to see if rings are rusted and struck or may be just struck from dried oil. I am surprised that the cylinder sleeve haven't rusted during this time of just sitting exposed. Freshly honed steel here in the South tends to rust rather quickly in a few months without being oiled every few months. This assumes the short block was good when you brought it from the Ebay seller.

50 psi on a newly rebuilt engine is way too low for this Briggs in my opinion. The 171400 series that I rebuilt last fall had only 45 psi before I rebuilt it. The only time it would even try to run was when gas was dumped directly in the cylinder and it would only run very slowly until some that fuel was burned. I was basically flooding it to get it to run any at all. Never could pull fuel from the carburetor.