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Discussion Starter #1
I bought a 7 hp h70 tecumseh snowblower engine but its not working. I cleaned the carb completly (even the small holes in the "screw") and turned the needle valve with the opened end toward the air intake. The guy that sold it to me said that he putted a new carb kit in it but that 1 seal was missing but I cant see wich one. I checked the compression by putting my finger in the sparkplug hole and turning the shaft and it popped off so I think its good. I checked for the spark too and it seemed ok. The oil level is good and the gas is new. The guy that sold it to me changed the fuel and prime lines on it. The motor dont want to start. The only I got it to start was by putting gas by the sparkplug before starting it and at full throttle, the motor was almost not turning, puffing like : puff puff puff puff pop puff... , the carb is leaking and its smoking white smoke a lot.
 

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Let's start at the beginning, you have a H70, there are some other numbers associated with that tell more about the engine, however, if it is leaking gas and puffs smoke when it does run the problem is most likely the carb float is not floating or the seat is not seating and the leaking fuel is in the crankcase and makes it overfull...bla,bla,bla. Sorry...BBQ&Beer dinner.
You mention it is a "snowblower" engine, is it not on a snowblower, the white smoke is oil, maybe it was tipped toward the spark plug or carb and some oil entered the intake or combustion chamber or exhaust area. The float could be a sinker, remove and shake it and listen for the slosh or put in some water. OOPS, My handler just told me to go back to my cage now. Have a good one. Geo
 

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Discussion Starter #3 (Edited)
Thanks for the help! I'll check tomorrow for the numbers but they are really hard to see because that this part is rusted. I already checked the float and she is ok (nothing inside) and no, the motor is no more on a snowblower (I bought it to make a water pump and air compressor to make artificial snow). Is my compression test ok or do I really need to meke myself a gage and a sparkplug adapter to check it? :thumbsup:
 

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Discussion Starter #4
The numbers written on it are H70-130227E SER 9124D but i'm not sure because that like I said before, they are really hard to see.
 

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Discussion Starter #5
I checked the compression again and she wasn't good and when I removed the carb, Ineeded to remove the primer line but when I pulled the line, the metal pin holding it to the carb just came out with the line so I really dont know what to do now.
 

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What exactly was the compression reading you got.Because of the compression release built onto the cam shaft,you should only have around 50 psi or so,I think.Just push the primer line fitting back into the carb body.The primer just pushes air into the float bowl.Do you have the service manual for the motor?If not,here is the link -----

http://www.barrettsmallengine.com/manual/tecumsehlheadmanual.pdf
 

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Discussion Starter #7
I just done the finger compression test so I dont know the exact pressure and for the prime, that's what I already done but even with the prime line unattached, the prime bulb takes like 1min. to come back in its iginal position so is this normal? THANKS YOU SOOOOOOO MUCH FOR YOUR HELP.
 

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If the primer is not attached to the hose and it takes awhile to expand,that is not normal.I wouldn't worry to much about the primer at this point.I have a 40 year old Tecumseh 6 hp without a primer and it starts just fine by using the choke only.After re-reading your original post - if the carb is leaking,the missing gasket could be the one between the float bowl and carb body,OR,it could be the little viton seat that goes under the needle valve and controls gas flow into the bowl.The service manual shows where it is and how it "HAS" to be installed.Hope this helps.
 

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Discussion Starter #9 (Edited)
Ok nice but what I wanted to say was that the primer was attached to its line but the line wasen't attached to the carb and today, I tried to start the engine with a 6.5amps drill but it didn't worked and I tried to poor gas in the sparkplug hole but it still didn't started but I think that I putted too much.
 

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It wouldn't make a difference,unless the the primer line has a clog inside it.Remove the line and push the primer bulb.Still slow to expand?Then the inside of the primer bulb housing has dirt in it,OR,the primer bulb itself has hardened from age.
 

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If you are absolutely sure that you have GOOD spark and decent compression,then the leaky carb has to be the bulk of your problem.Remove the carb AGAIN,and use brake parts cleaner to spray every little hole you can see and often can't see.If you have an air compressor,blow out all the passages you just sprayed.Make sure you remove the idle air screw and the high speed needle from the the bowl nut to clean those passages also.Pay special attention to the holes in the bowl nut!I would recommend Tecumseh part# 631021b carb kit which has a needle,seat and bowl gaskets.Lightly seat the idle air screw and back it out one full turn.Lightly seat the high speed needle and back out 1 1/2 full turns.These will be the starting point and will need small adjustments to make the engine run perfect,after you get it to start.
 

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Discussion Starter #13
I dont think tht the engine compression is good that I said. I hve a tight budget (student) so what would you recomand to me? buy an other engine or repairr this one? How much do you think that it will cost me if the compression is bad and that I need a new carb kit need?
 

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If you don't have a compression gage,some of the chain auto parts stores will let you use one for a small deposit.Personally,I think the carb is your biggest problem.The 631021b kit is around $5 at any lawn mower shop or on line from eBay. Maybe the man who sold it to you would give you some help?What do you plan on using it for once you get it running?The manual will answer most of your questions,and some one on here will be happy to answer the rest.
 

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Discussion Starter #15
Thank you very much for the help, I'll check if I can find a compression tester this week and i'll very probably buy a new carb kit. The man that sold it to me is like "its your problem" so no help from this side. I'll use the engine like I said before to power a 3gpm pressure washer pump and a 2 hp air compressor (7-8 cfm) to make artificial snow (www.snowguns.com is a very good forum for snowmaking at home or even commercial setups). These 2 pumps will be powered by belts and require a total of 3.5 hp = 7 hp gas engine.
 

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From the serial number,this engine is either a 1969,1979 or 1989.I would guess a 1979 without seeing it.Good luck Dan,keep us posted on your progress.
 

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Thank you very much for the help, I'll check if I can find a compression tester this week and i'll very probably buy a new carb kit. The man that sold it to me is like "its your problem" so no help from this side. I'll use the engine like I said before to power a 3gpm pressure washer pump and a 2 hp air compressor (7-8 cfm) to make artificial snow (www.snowguns.com is a very good forum for snowmaking at home or even commercial setups). These 2 pumps will be powered by belts and require a total of 3.5 hp = 7 hp gas engine.
The simple "country boy" compression test is, (without all the modern safety stuff attached) pull the starter rope, if it picks up the mower, it is OK. Have a good one. Geo
 

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Discussion Starter #20
Today, I checked to see if the head gasket was ok. When I unscrewed the bolts, 2 0f the eight bolts broke. The head gasket (wich I realized is more like a metal plate) seemed ok but now, to be able to screw the head bolts again, I drilled smaller holes in the bolts so that I can screw new ones in the old ones. What's the problem if its not that? could a bad carb kit affect the compression or is it an other seal or a valve in the engine that cause this to happen?
 
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