# B&S 35 HP Fuel Pump Problems



## Tater50 (May 26, 2012)

On a Scag Mower: 
Model 613177: Bought this one w/blown head gaskets; Reworked heads;
valve job; reinstalled; adjusted valves 1/4" beyond TDC; New dual fuel pumps; gas in tank; compression test, above 150 both cylinders.

Problem: cannot get fuel pumps to work; understand that they work off of the crankcase vacuum. Engine will run as long as I spray gas in carb.

Any ideas?

Thanks


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## Basementgeek (Feb 7, 2005)

Hi and welcome to TSF

Check to make sure your crankcase breather is clean and working correctly.

Also check the seal around the dip stick. 

BG


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## Tater50 (May 26, 2012)

Will do; thanks for the info


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## Basementgeek (Feb 7, 2005)

I did assume that you have checked the fuel line and filter already to make sure that they are clear.

BG


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## Tater50 (May 26, 2012)

Further Problems: This is a water cooled engine. Here is what I have done so far. When I purchased mower it had water in oil.

Had heads reworked (do not know how they determined there were no cracks, but shop said they were OK)valve job

Reinstalled heads w/new gaskets (expensive...$80 a pair) 

New fuel pumps but NO fuel to carb

Used gravity fed tank & engine ran smoothe for 2 minutes; when it got warm started to hesitate & popping like minor back-firing. Ran it for about 5 minutes; noticed NO leakage.

Turned off & checked oil (oil was new) very milky; so I am getting water in the oil. 

Does this sound like a head gasket, cracked block or cracked heads.

Thanks
This is a project I am working on during the summer, so NO real hurry.


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## Tater50 (May 26, 2012)

Update: purchased some radiator & engine dye & used a gravity flow gas tank from an old MTD mower; started up the engine & let it run for 5+ minutes.

After it warmed up; upon inspection noticed that dyed oil was coming out of both heads. Will remove & inspect; maybe the mechanic made a mistake.


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## SABL (Jul 4, 2008)

Check the heads and block with an ultra violet light after removing the heads. Cracks will be easier to spot.

Also look for "tracking" (a groove) on the head and block mating surfaces. The high pressure gasses can act like a cutting torch when ignited.


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## Tater50 (May 26, 2012)

SABL: I called a head shop & that was going to build a gig to check for cracks, but due to the fact that it was further away, I chose another one; I think they only did a visual; live & learn; so therefore, I am going to take them to the first head shop.

Thanks for the info.

Any idea where I can get after market B&S gasket sets? Man the head gaskets are $80 a set?


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## Basementgeek (Feb 7, 2005)

Did they mill the old heads? I wonder if if they could have warped any.

BG


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## SABL (Jul 4, 2008)

NAPA may have the head gaskets.....never checked the prices but they do carry small engine parts. You never know, Auto Zone or similar stores may also sell small engine supplies.....

I stay away from lawn equipment dealers if I can. Learned a lesson many years ago when I ordered parts for a lawn tractor and was charged more than $4 for a common bolt that was only about 30 cents at a hardware store. I just ordered the part #s on the list......was real shocked when my son picked up the order and I saw the prices. Never again......

Alas, with a watercooled engine I'm thinking it was not properly winterized and the block and/or heads may be cracked. Learned a hard lesson years ago when the forecast was for 35F overnight. I knew it was getting close to winter and went out the next morning to drain the block on a 260HP Mercruiser. Pulled the radiator hose and found ice crystals......the cracks in the block were easy to feel when running my fingers along the sides of the engine......:sigh: A day late and way more than a dollar short......


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## Basementgeek (Feb 7, 2005)

I think once you get to that size engine with water cooling probably not going to find many after market parts around.

Do a google search is about all you can do.

BG


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## Tater50 (May 26, 2012)

Basementgeek said:


> Did they mill the old heads? I wonder if if they could have warped any.
> 
> BG


Heads were milled & grinded valves; said they saw no signs of cracks; I only think they did a visual inspection.

Of course; the block could be cracked; will proceed w/the breakdown & LYK what happens; these 35HP in a mower are not common & a new engine is pretty steep; so it is not a 911 situation & I do not have much in the project for this caliber mower.

Thanks for the incite.


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## SABL (Jul 4, 2008)

I think new engines are ~$3,000....block is $700. Depends on the condition of the mower......Skags are not cheap!! How many hours on the mower??


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## Tater50 (May 26, 2012)

SABL said:


> I think new engines are ~$3,000....block is $700. Depends on the condition of the mower......Skags are not cheap!! How many hours on the mower??


1786 hours


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## SABL (Jul 4, 2008)

If it has been maintained fairly decent you may get that many more hours out of it. I couldn't afford a Skag and went with Toro. 7 seasons and 335 hours......it will be around a lot longer than me. 

Do as BG suggests and Google for parts.....maybe check out the hits that lead to eBay. Victor or FelPro may make gaskets for your engine.

Let us know if you find anything.....


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## Tater50 (May 26, 2012)

Have not been able to find any parts; but let me pic your logic.

My logic: after warm up; I saw oil leaking from all around the lower section of each head; that indicates to me that the gaskets are not sealed or there is a tremendous crack on both heads; if so, that would have been sort of visible when milled.

Also; when the mechanic reinstalled the parts; he left off one intake gasket & water was blowing by and coming out the exhaust; I repaired that & no water coming out of exhaust.

My logic is to proceed with the head removal & send off to proper head shop for inspection; but how can I check for cracks in the block?

If the block were cracked; wouldn't the leak be lower than the joint where the head attaches to the block? Odd that both leaks are at the head joints at the same area.

BTW: thanks for all the input.


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## SABL (Jul 4, 2008)

If you have an ultra violet light (black light) you should be able to use it to spot defects after running the dye through the engine....provided it was flourescent dye.

Now that you say the mechanic forgot an intake gasket I'm wondering about the mechanic....that's a pretty big mistake. Did he torque the head bolts?? In the right sequence?? Increase the torque in increments until the final torque was achieved?? 

Let me see if I can find the parts diagram in my history....or do a new search. I had 'em pulled up the other day.


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## Tater50 (May 26, 2012)

Update: Removed heads & took them to a seasoned head shop; Frank performed vacuum tests on both intake/exhaust & indicated that the other head shop had done a good job.

He did not see any indication of cracks, but has a machine that he will jig the heads on & rule out any cracks; $80 for both, but that is better than $1000 for 2 heads.

He is a very experienced Head Repair Technician; used him in the past, should have used him first, but at the time was not convenient. Anyway: I showed him the old gaskets & he told me to use a copper spray when I installed the new ones. Hang them up & put a light spray on both sides. He indicated that these were prone to fail; FelPro had sent out a memo to coat them.

He also indicated as you all that proper torque sequence is important.

Went to NAPA & O'Reillys & they have no B&S parts for anything higher than 20HP; I will keep google warm & see what I can find; $80 for a pair of head gaskets is steep; of course I am going to need the intake & exhaust to do a good job.

Will keep you updated.
Thanks


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## ___TQC___ (May 23, 2012)

It looks like the head gasket is $27.50 here Briggs and Stratton 613100 Series Parts List and Diagram : eReplacementParts.com


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## SABL (Jul 4, 2008)

> There are multiple versions of this engine
> to show parts for your engine only,
> enter your type number:
> to change your type number click here:


Good find on the parts.....Tater50 will have to get the type number to confirm the parts and prices.


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## Tater50 (May 26, 2012)

Today's update: Frank's Head Shop finished w/the pressure testing for leaks; found the heads to be in perfect working order; did a vacuum test yesterday & the valves were seating great.

By ALL accounts, our shop mechanic must have torqued the heads down not in sequence & thereby caused the gaskets to not properly seat.

Thanks for the parts info; got the parts ordered, but it will be Friday before they arrive; will proceed with reassembly Sat or Sun.

Thanks for the support; great forum.


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## SABL (Jul 4, 2008)

:thumb:....let us know how it turns out.

The mechanic will have to follow the sequence *and* increase the torque in small increments until the correct torque is reached.....and recheck all bolts for the correct torque when finished. If he is using a micro-torque and never sets the dial back to zero before putting it away, the torque wrench will not show the correct torque (click when torque is reached) and may be way low. I set my wrenches back to zero as soon as I am done.....or if it won't be used within a very short time frame.


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## Tater50 (May 26, 2012)

Torque Wrench: did not know that but logic would dictate that the constant pressure would have an effect on it; anyways; I bought a new one for the Mechanic to use, so I am going to reassemble slowly; will follow the procedure; I was thinking of getting the bolts just snug then crisscross pattern in increments of 10 inch lbs until 350 is achieved.

Thanks


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## Tater50 (May 26, 2012)

Bingo: got a great update.
Frank's Heads indicated for me to use copper coat on the installation of the new gasket set. Each gasket is 2 metal gaskets riveted together; my logic, break one of the rivet, pivot them apart & spray all 4 sides.
Installed heads; changed ALL the lines, fuel shutoff, inline filter & still could not get any fuel...........

Talked w/one of the town's mechanics & he had the same problem w/a customer's mower, traced it down to ethanol buildup in the crook of the gas line............

That got me to thinking; I changed ALL the lines, well NO, I did not change the 2 short lines from the valve cover to the vacuum part of the fuel pump; guess because our shop mechanic that had previously worked on it had indicated that ALL lines were OK.

These 2 lines are about 5" long, the inside one that links to the inner fuel pump has 2 angles in it; the outer only one angle. I pulled those off, tried to blow thru them w/my mouth........clogged; just as your replies indicated, clear the lines; should have done this work myself, but I was playing softball out of state. 

I took a a long wire & prodded one & a worm like semi-solid mixture came out........about an inch long. The line from the y joint of the 2 fuel pumps to the carb was caked with varnish; replaced the line. 

Bingo: started right up.............Operated it for 30+ minutes; every once in awhile it has a stutter; will try some gas/carb cleaner; if it does not clear up will probably have to take the carb apart & rebuild.

Prior: the engine had water in the OIL; well, after operation, oil is clean, no water.

Thanks for ALL the support; this was a project Mower and as was indicated the fuel problems was nothing more than ethanol/varnish clogged lines.................. Glad I did not buy that expensive Electric Fuel Pump!!

Investment:
Scag 61" 35 B&S Water Cooled Mower: $400
Reworked, Inspected, Pressure Tested Heads: $320
Gaskets, oil, filter & $70 for shop mechanic's work $200
Gaskets, copper coat, high temp sealant, oil, filter, 
Bearing set front wheels $300

Total in case I forgot something like bolts, nuts $1300
Would have been $200 less if I had of done the work!!

Great site, great input!!!!!!!


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## MrChooks (Apr 19, 2008)

Tater50 - a hearty very well done on this one - sounds like you have a great deal on what would be a very expensive mower.

Sorry, I am coming in a bit late on this thread here. Given that you located all that crap in fuel lines and you have now cleared / cleaned / replaced them all - if at all possible - I would remove the fuel tank and wash it out thoroughly. 

With the kind of crap you described, it sounds like a combo of mowing debis, dust/mud as well as old fuel residues - so if there is more of that crap in the tank (and if the previous owner didn't use a strainer funnel to refuel - there almost certainly will be) it will find its way into your fuel lines filters again.


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## Tater50 (May 26, 2012)

Thanks: did remove all fuel & clean the tank; I think I may have to rebuild the carb if I want to get the occasional hesitation out, but will look into that later; running real decent right now.

Thanks for the input.

I went on R&R in Sydney in 1971 when I was stationed in Viet Nam; took about 200 pics of the local zoo. Loved it!!


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## MrChooks (Apr 19, 2008)

Tater50
As I am not familar with Scag Mowers - I Googled them and was amazed to see that a new 61" cut job costs $14K - hell - my car isn't worth that much - so this is one serious commercial grade piece of gear and you have done really well to get one & get it going for $1300+/-.

Without wanting to make more work for you - but given that commercial grade gear like this, with reasonable maintenance, should give about 3000 hrs before it needs a major overhaul - can I suggest you do a little preventive maintenace on your "expensive" hydraulics as well. 

Nothing too hard - just a clean out of the oil tank, new hydraulic oil filter, new hydrauliuc oil and a check on the condition of / repalce defective the flexible hydraulic hoses - and you're "mega mower" should be good for years more. None of these items should cost too much - but a mower like that deserves a little TLC


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## Tater50 (May 26, 2012)

Great heads up Mr Chooks: will do; I have a Troybilt ZT 50" that operates great that I can use, so I will follow your advice & finish the job.

I have put some Seafoam in the tank; will run it thru to see if it helps the occasional sputter.

Thanks


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## MrChooks (Apr 19, 2008)

Once you have that "growler" Scag completed & going - pls post us a pic. 
With a mower like that I could do all my lawns with about 10 passes and in about 10 minutes:grin:


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