How to remove the cylinder head from a Yamaha 50HP four stroke outboard motor
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- čas přidán 17. 11. 2014
- In this video I remove the cylinder head from the Yamaha 50HP four stroke to begin investigating why the compression is low on cylinders one and two. We go through the basic procedure of removing the carburettors, timing belt, oil pump, fuel pump and then the head itself.
See this video for the process to remove the powerhead from the outboard before removing the cylinder head:
• Removing the powerhead...
Getting ready to replace my carbs with a better set. Your video was very helpful (as all of them are!) . Thanks, again!
Thank you for another great video.
VERY GOOD VIDEO, Thank you for make this VDO and show all step how to check and remove.
A++++
simpsonfishing9 Thanks mate, appreciate your comment. :)
your videos are great,want to change pistons in my mercury 200 2 stroke .just need to get the fly wheel off first.
Love your videos, any reason as to why you don't use power tools when removing nuts and bolts?
Thanks mate. It's a good question about using hand tools, I think it is more out of habit that anything else. I have a nice electric 3/8 impact gun that is great for engine fasteners etc, but there as so many times that you can't get the body of he gun into position that I just stop using it for anything.
Hi Mark, sorry I accidentally removed your comment instead of hitting reply on my phone. Doh! It is common to use an extra number of degrees as a way of specifying torque, and head bolt torque settings are quite high, even in aluminium. In fact twice now on my F50 I've stripped the aluminium getting it up to spec, but that is problem due to a previous overheat. If you are worried, I would try to find a similar motor (with an identical bolt diameter) where the spec is in pound feet just to give you a sanity check.
I really like the videos
Thanks mate. :)
Do you have a video on rebuilding carbs on a Yamaha 50 tlrc carb 4 stroke (2004) model ?
Wonder do they make high performance cams for theses type 4 stokes?
do these (FT50BET) motors have a restrictor plate like the newer do?
Mis felicitaciones amigo, mi agradecimiento inmenso por su aportacion desinteresada que nos sirve de mucho a los que no tenemos oportunidades de encontrar estas informaciones valiosas, sabe tengo un fueraborda diesel Yanmar 36hp y su mantenimiento es carisimo aqui en Peru y le rogaria de todo corazon si tiene por casualidad algun video relacionado con este fueraborda diesel Yanmar , nosabe cuanto me ayudaria, muchas gracias 👏👏👏👍⛵
Hi Stu, great work on the videos mate! I've learned heaps and they also keep me entertained on the way to work :)
Not sure if you've got time to answer questions here these days but thought I'd ask...
I've got a Mercury 50hp 4 stroke from 2000 with quite light oil seepage from what looks like the lower part of the head gasket behind the carburetors. Compression seems ok on on all 4 cylinders so I was wondering to inspect the head and change the head gasket will I have to completely lift the powerhead or is it possible without?
Cheers mate, keep up the good work!
Hi Andrew. It depends a lot on the outboard. There is no real reason you need to remove the powerhead other than clearance around the lower cowling. Sometimes you can't get to the lower head bolts without the motor removed. This video on a two stroke head gasket hits this problem a bit, but it did come off in the end with the powerhead in place. czcams.com/video/NVLHJSuVHA4/video.html
Great, thanks. Apart from the linkages, the engine layout on this Mercury 50hp is very similar to your old Yamaha 50hp so those videos have been a great help. With the Mercury I can remove much of the lower cowling really easily, so hopefully I'll be fine. Just waiting for the gasket kit to be delivered, I figured I'd get the full powerhead gasket kit just in case. Looking forward to getting the boat back on the water in the spring up hear in Stockholm... still a few months away :( Thanks again for the help, appreciate it.
What does a 6 pack cost down there these days? It's been a while since I was last in Oz. I'd like to send you some beer money to get you through the next couple of videos... let me know the best way to donate.
Thanks for videos, by the way I have a question about 1964 Elgin. Do you think can find a parts for the kind of boat motor?
Hi Jesse. I haven't seen any Elgin parts listed on the sites I normally use, but they must be out there. I've never worked on one so I haven't tried myself though.
I have a genuine question.. The crankshaft rod was giving knocking noises, when I ran the motor. So I went ahead and changed the crankshaft and its bearings. I ran the motor for about half an hour after putting them all back together. Then it starts smoking up a bit. Along with the control box sensor beeping going off until I turn off the engine. Next thing you know, the engine's flywheel froze and unmovable. My question is, what was the cause of it and what does it mean? Please let me know, thank you.
Hey Stu, thanks so much for all the great videos I have learned so much from watching them. As a first time boat owner they have been great to watch. I have a a 2002 t50tlra with a gouge at the top of cylinder 3 and these block be sleeved. Thank you in advance for your help.
Great Video today, I am replacing the block of f115, and re use the head. Do I need to planning the head/block? Thanks.
At least use a straight edge and feeler gauges to check it is flat in every direction.
I have a Yamaha 25hp four stoke I'm working on, it runs fine has good compression but there's a tic noise coming from the cylinder head area, I replaced the fuel pump as suggested on a forum but it didn't do anything. Any advice or possible causes would be appreciated, thanks
Hi Paul, before a four stroke I would be checking the valve clearances. If they are too loose they can make noise czcams.com/video/aVBWNAhs3XU/video.html
Lo felicito me an enseñado mucho estos videos muy buena enceñansa lastima q no estan traducidos al español
Hello I like your videos although I do not do much off the marine stuff but I like to see how things work, I am a car mechanic here in the UK so used to mainly working on 4 cylinder engines, and motor bikes, having watched a good few of your videos I see CDI units are used for the ignition systems but are there any fuel injection outboards ? and if so will you be breaking out an oscilloscope as I have found it to be a without peace of kit over the past few years.
Yes, all new four stroke outboards are fuel injected. I've been meaning to do an oscilloscope video for a while. I'd like to cover spark and injector pulse.
Perfect thanks
Hi
How can I get a service manual for Yamaha 50hp injector
Thanks in advance
Hey boss,
Just wondering, is this F50 an interference engine? It looks like if the timing belt goes, you will in fact bend valves/damage pistons. This is the 996 block? Thanks!!
That's a good question, I'm trying to think back. From what I just read then it looks to be non-interference so if your belt has failed you may be okay.
Hello I need some help on my 2000 70hp suzuki it start when I spray starter fluid then it runs for a long while till I turn the key off. But when I start it again Ill have too shoot starter fluid to start the motor going. The other thing is I have to remove a vacume hose from the cranckshaft in order for this motor to start. When I attach that hose the motor wont turn over till I remove the vacuum hose and spray starter fluid then it will run as long as I want.
It not normal but don't know why it does that can you help me? Suggesting anything?
Sincerly Ed
Where does the vacuum hose go to? Is it for the fuel pump? Is there fuel in the carburettor bowls when you are trying to start it? Have the idle jets been cleaned on the carburettors?
i have heard lot about restrictor plate for f50 yamaha ...but i have the same engine like you year 2000..i couldn't find it ...since you have gone thru this engine can you tell me where it is? or does it have it or it comes later years..thank you very much
Hi mate. Sorry I missed your comment. Notifications haven't been working for me until now. Hmmm, I never saw anything labelled a restrictor plate on my outboard. Do you know what it is designed to do?
Hello Danger i know this is quite a old video now. But im hoping for alittle advice here. Im looking at buying a suzuki DF 25 V-Twin 4 stroke motor from 08. I got a fairly good price so im 90% sure im gonna get it tomorrow when i go out and have a look at it.
My question is - is there a possibility for you to make a overall video of V motors. And is V motors any bad or good in the boat world. ?
I've heard it was a good motor, it sounds and looks pretty good aswell, but will you say good for them ? Anything to look out for or is it just like normal outboards ? :)
Thanks in advance cheers ! :)
+SirTrampe All V motors tend to be quite compact and balanced which is good. The Evinrude I've been working on in the recent videos is a nice solid V6.
Okay thats nice, so i shouldnt be worried about going over to V motors :)
What year and model is this power head that you are working on. Thanks for filming your repairs. I am currently in the process of diagnosing low compression on my 2000 Yamaha 50 4stroke - T50 TLRY. I think it is basically the same as the one in your video. Please continue filming the rebuild for this as it has been very helpful so far
Hi there. From memory it is a F50AET. It has a U designation for the year which puts it at 1996. (www.simyamaha.com/Model_Code_Reference_s/1798.htm) I'm glad you got some value out of the video, it gives me the motivation to push on with the head. I also need to take the crankshaft out as the spline is worn.
hi dangar i have a Yamaha 40 HP 2 t from 84, (3 cylinders) cylinders 2 do not move, spark spark plug, have switched colli around, luckily i'm about to die in the project, what would your approach way be?
It could also be the trigger wire going to the coil.
Hi Stu,
Thanks for the brilliant videos on the Yam 4 cyl 4 stroke. My son bought a boat and had one (2000 model) thrown in for free as it was 'seized'. Turned out that water had got in the intake box, sucked in to cylinder 4 and bent the conrod. In one of your videos you said you were going to show a breakdown of the carbs but we can't find it. Did you ever get round to doing it? Would be great if you had!
Cheers Barry
Hey Barry. It's an old and poorly made video, but this one I think was Yamaha carbs czcams.com/video/ye_Ui9D8dBE/video.html
What type of torque wrench do you have? I need to get one
Hi Marty. Mine is a Kinchrome. Reasonably good for the price.
Hi there I have a blown head gasket on my 4 stroke 100hp Yammy , Does the power head need to come off to get to the head gasket ? Or can it be done as is
Often it can be done with the powerhead in place. Removing the lower cowling can help though.
Thank you
Stu , how much would I expect to pay a marine mechanic for replacing my head gasket? Symptoms- milky oil, cylinders compression 140,140,140 and 120 , engine still runs doesn’t over heat and didn’t overheat , only saw the milky oil after I did a service overwise I wouldn’t have know
Hi what is the moments fore the cylinder head bolts and the kamshaft
Can recall now, you should be able to get a PDF service manual from readmanual.com
hi i would like to learn more about the out board engines do you teach classes
+dean walcott If you head over to my channel page you'll see there are videos on most parts of an outboard now. I don't run classes as such, but if you need more information on a particular part feel free to ask any questions you have. What do you live?
+Dangar Marine ok am from jamaica
+dean walcott Nice. Would love to visit one day. :)
I really like
Thanks Jose, glad you enjoyed. :)
This Yamaha has the same power head as the '98-'99 Mercury/Mariner 40/50 hp four strokes, right? Had one of those and this looks bang on exactly like it. It was an absolute nightmare. So unreliable and sensitive to air/water temperature changes - which is unfortunate when you live in Norway. Swapped it for a brand new e-tec and had the first problem free summer in ten years. Never going back. Great video though.
Yes, a lot of people swear by their e-tec motors. I've never had a lot to do with them but owners seem to love them!
Dangar Marine e tec I believe are a horrible motor . as a tec I see more of those than anything else
SLM Early 4 Stroke Yamaha engines had issues. I purchased an early 115 Yamaha EFI and it had ECM issues which would cause it to shut down unexpectedly. It also would sludge the recommended engine oil prematurely because the engine didn’t run hot enough to evaporate condensation in the crankcase. It was also a pig getting the boat up on plane. I had been a long time Yamaha 2 stroke owner when I thought I was trading up to get the 4-stroke. I love older 2 Stroke Yamaha engines but I’m not in a hurry to buy another 4- Stroke.
Really enjoy your videos but kind of difficult to hear. maybe grab a clip on mic.
gday mate thats the problem with working on second hand engines the more you look the worse it gets very frustrating and depressing sometimes ,thankfully i have only had 2 stroke engines so far but i suppose the day will come when we wont be able to buy them anymore (coming soon) and then it will be all four stroke
Yeah, this outboard was a really trashed. It had been sunk about four times during its life. It probably wasn't worth the effort but it was good experience. At least that's what I tell myself. ;)
Hello did you now how to set time belt
This video goes through that in detail czcams.com/video/o9tau2K3ej8/video.html
Danger, why do you need to remove the flywheel/magneto assembly. Why not just mark the belt and cam sprocket with white-out and then remove the cam sprocket?
Thanks
From memory you don't need to, but I was following the procedure in the service manual at the time and that was step one. Perhaps the procedure was part of a larger teardown and therefore had unnecessary steps for this job.
Hola adonde estan localisad
Sydney, Australia.
Ok my freim
Towards the end,yeup if you what up ahead its harder to enjoy jobs you don't get paid for.
👍🇨🇦😃