OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines fuel to oil ratio for Mpsport craftman 435

Leo, the dipstick attached to Mark's oil filler cap was added in about 1980 - before that the filler cap hole acted as a level hole. That is, if your filler cap does not have a dipstick attached to its underside, in theory you are supposed to fill the sump until oil reaches the top of the hole. In practice I find if I do that, when I park the mower after use, it leaks some oil from the filler hole and makes a mess (the filler cap does not usually seal all that well).

Hi Mark, Grumpy and guys

Thanks for your reply, and I will fill the oil today. I will give you the feedback tommorow.

Grumpy I am not sure why you would offer up that info in this instance. Could well get reports back of a motor chock a block full of oil.



It is like your car Leo.
Check the oil by using the dipstick.
Good fresh clean unleaded petrol in the fuel tank.

Bob, Leo posted a picture of the filler cap area on his engine, and it seems to be one of the pre-1982 low ones that had just a filler plug with no dipstick. Those ones are supposed to be filled to the brim - in fact if you drain them and then pour in the required 600 ml of oil, the oil reaches right to the top of the recess and you can't fit in any more. Just to be on the safe side though, I warned him that if he has a dipstick rather than just a filler plug, he must only fill it to the level mark on the dipstick.

Hi Grumpy/Bob

I understand what did the Grumpy say, and the good news is that my engine has the dipstick similar as Mark's. And the question is where is the full mark line(see photo, i refer to the Mark' pic)?
Because I added about 300ml oil, and the dipstick indicated nothing on it. I will add more(little by littel) oil tomorrow and make sure not over filled.

The top mark (the one you are asking about) is the full like when the dipstick is fully screwed in then pulled back out to check

Leo, Joe is correct as always of course. The point about screwing the dipstick all the way in, then unscrewing it and reading the oil level, is important. Honda dipsticks are read by resting the thread against the crankcase without screwing it in, so you can't use Briggs technique on a Honda or vice versa.

Youve got a PM Grumpy

Thanks Bob, I've answered it.

Hi Grumpy/Guys

Thanks for your help!

The good news is that the engige could start now after I filled the oil, not overfilled. The problem is that it still shut down 5 ~10 minutes later, and the engine is very hot(yellow arrow side)even the red circle side is hotest. I left it cool itself about half an hour. It could start again and worked around 5 ~ 10 minutes again, then engine automatically stopped. That means the engine only could work 5 ~ 10 mins every half hour. What is wrong with the engine?

You should start by looking for cooling problems: restricted air flow from the fan through the cooling fins, especially on the cylinder head, and an obstructed muffler. The classic cause of both problems is a wasp nest that has been built while the engine was out of service for a long time.

If it is neither of those problems you will need to look at whether the mixture is lean or the ignition system is breaking down when it gets hot.

Leo, it sounds like your engine needs a good overall service.

Im sure you would like it to start reliably and run well for this growing season and more to come.

If that engine came to me, I would flush out the fuel tank, clean the carby, clean the air filter, clean the spark plug or replace it, clean the magnet faces & magneto armature faces and reset them, clean all excess carbon from the head.

Plus check the things Grumpy has said & more.......

Joe earlier on offered to service it for you.

If you want to service it yourself step by step we can do that to.

hi Grumpy

I totally agree with you that it is most possibily that the cooling system causes the engine shut down. Could you please advise me the detail how to check them? Thanks

Hi Mark

Thanks for your sugestion, and I do not know how much should I pay for Joe. I would like to try to service it by myself. The question is that where should I get the manual of this engine.

Sorry but I think you should just pay what it costs and get it fixed by someone that knows what they are doing.
You are now more than capable of checking the oil and keeping on top of that, so once you have it serviced and fixed it will be good to go for quite a while with just regular oil top ups.


I appreciate that you want to learn. I would actually welcome that you do that. If you google or youtube about how engines work I am sure that you will come up with hours and hours of reading and watching. You need to understand how it works before you can fix it. Otherwise you are flying blind. Learning takes time.
The issue you are having could be any number of things.

Sorry leo, but the post with the arrow and circle got me. The yellow is the back of the crankcase and the red is the muffler.
Yellow, yeah that gets hot, not being experienced you would not be able to tell too hot, from hot, from not hot enough. If the motor has been running for a few mins, too hot to hold your hand on is normal.
Red, thats the muffler/exhaust. Hot hot very hot, dont touch.





Cheers, Bob.

Leo, to go through the steps with you to find and fix your engine fault is likely to take quite a while, you will have to buy tools if you don't have them, and the mower probably won't be in running order while all this is going on. If you want to learn about mowers, this is all do-able and we can give it a try. Expect it to take quite a lot of work and frustration, and cost more than getting your mower fixed by an expert, or throwing it away and buying a second-hand mower in proper working order. You will also have to follow the process closely and take the steps you are asked to take, without making your own experiments or leaving out steps. It is your choice to make. We've gone through similar processes several times before at Outdoorking, and succeeded, but we've also occasionally had someone drop out along the way, and at least once the person was very unhappy and noisy about it when he made that decision.

Hi Grumpy/Bob/Guys

Thanks for your reply and suggestions, and I will start to learn now.

Leo, please post the long string of numbers stamped on the cooling air cowl of the engine - that is, the pressed steel cover over the upper part of the engine, with the Briggs sticker on it. The numbers are usually on the vertical left side of that cowl when viewed from the operator's position, near the top. The numbers will be in three blocks, marked Model, Type and Code. We need all three blocks. That will give us some details of the engine, including its date of manufacture. Then I'll be able to suggest an overhaul manual for you to look at as background, while we go through the maintenance process. (The Briggs overhaul manuals are all available in the manuals section of this site - we can talk about it when you've posted the string of numbers.)

Grumpy, thanks. And I will post the pics requested tomorrow.

Hi Grumpy

Here are the photos, and I could not find the long string of numbers stamped on the cooling air cowl of the engine.