Yamaha f250 Start Up Noise

[zenoahphobic]

trust me, its the variable timing sprockets.
sometimes after sitting they bleed down and chatter like crazy at startup.
dirty/clogged OCV filters make it worse.
find a trained tech that has worked with Yamaha's variable timing system.

But does the noise indicate premature wear or damage.

I know of cars where the cam and tappets etc make a racket on start up. The establishment say it is normal. I have found that the Chinese oil pump fitted to a particular engine does not bring oil up to pressure at idle. Guess what new cams have to be fitted after expiry of warranty.

On the car I have I did not accept this noise from the outset and was lucky enough to find a new old very old stock oil pump used on earlier variants of the engine block.

And noise went immediately away on startup, and never returned even after a further 200 thousand kilometres! (Another two times warranty kilometres)

[zenoahphobic]

And Townsend being a motorcycle enthusiast would agree, never accept excessive overhead noise. In motorcycles this always indicates trouble.

[zenoahphobic]

I'd be prone to just go with whatever Rodbolt says....he's the doctor on these motors!...

There is no doubt Rodbolt is highly skilled and experienced in diagnostics.

We have not heard, seen or even know where the noise is coming from. Such is the nature of Forums, so we go out on a limb.

To diagnose accurately we need many bits of info. Just like finding a position we need at least three coordinates. Modern GPSs use many more.

Because of the increasing complexities and subsequent large increasing cost in diagnosis and repair we are needing to be more cautious.

I remember the brilliant Dr House coming up with an immediate diagnosis: he's got ......put him on ....... Dosage of .....
It was only the brave that would ask him: but what if you are wrong. House would reply: he will die from the.....I just prescribed him!

The outboard equivalent is large unnecessary cost and maybe loss of engine. So the message (often given here) is get these beasts thoroughly checked out by competent people.

[boscoe99]

Remember the good Doctor Frist who diagnosed a lady in a coma from viewing her on television? What a fool. He was proven to be wrong.

Are you sure about three coordinates being needed to determine a position on earth?

[TownsendsFJR1300]

W/O having ANY experience with the variable cams with oil pressure and of course Rodbolt having it, I would pay very close attention to his posts. It may be something else but your getting the most likely culprit.

Certain BMW motorcycles have an oil pressure cam chain tensioner with NO GUIDES in a certain spot. Works great with oil pressure and running.

On initial cranking, it was NOT uncommon to jump a tooth on the cam chain (not good). BMW's fix was to later put a guide there. Of course that wasn't under warranty and you had to pay for it, duh...

Anyone who's worked on a particular engine (especially often) can tell you the quirks, issues, un-common noises associated with it.

[zenoahphobic]

Remember the good Doctor Frist who diagnosed a lady in a coma from viewing her on television? What a fool. He was proven to be wrong.

Are you sure about three coordinates being needed to determine a position on earth?

A tripod stands on its own. Two pieces fall and rest. Longitude and latitude (2 cords) only go so far. Try shooting down a plane or torpedo a submarine with only two coordinates.

[rodbolt17]

and whats funny, I am the only one posting on this thread that's actually had the sprockets apart. so far since about last may I have done 11 4.2 and 5.3 block/head replacements. that's just this summer.

trust me some chatter some don't.

find a real tech that has real world experience.

[shotgun16]

Trust me Rodbolt, I very much value your opinion, I have seen and benifited from your extensive contributions to discussions on this and several other sites. When I see your screen name, I immediately take note. What I am wondering, in your experience, does the chatering you described pose any, threat to the engine if it persists after filter change for reason you described?

[boscoe99]

A tripod stands on its own. Two pieces fall and rest. Longitude and latitude (2 cords) only go so far. Try shooting down a plane or torpedo a submarine with only two coordinates.

So if I call the Coast Guard for help while at sea I need to give them three coordinates to come and find me? What is the third? I want to be ready if and when I need to make the call.

[boscoe99]

and whats funny, I am the only one posting on this thread that's actually had the sprockets apart. so far since about last may I have done 11 4.2 and 5.3 block/head replacements. that's just this summer.

trust me some chatter some don't.

find a real tech that has real world experience.

I don't think so. I take stuff apart just to see what it looks like inside, even when it is not meant to be opened up. Oil control valves, belt tensioners with hydraulic snubbers, rectifier/regulators, you name it.

Now I will say that the variable cam shaft mechanism can be a bit fiddly. My own Ford F150 truck has this mechanism. After my first oil change, when I was getting money from an ATM, the damn engine was clattering away. The building was causing me to hear the noise. Sounded awful. WTH?

A bit of research on the innerweb told me about the need to use semi-synthetic oil to make the problem go away. I believe Ford even issued a technical bulletin about the problem. I was a non-believer. Changed the oil and voila. No more clattering noise. No harm, no foul. It is just the nature of the beast.

[zenoahphobic]

Remember the good Doctor Frist who diagnosed a lady in a coma from viewing her on television? What a fool. He was proven to be wrong.

Are you sure about three coordinates being needed to determine a position on earth?

So if I call the Coast Guard for help while at sea I need to give them three coordinates to come and find me? What is the third? I want to be ready if and when I need to make the call.

It is the 3 dimensional property of space. The earth was flat once( many experts years back said so).

Sure the Coast Guard will try to find you with just the two coordinates, if you are afloat that is. But the wise would use a "third" which would be factoring in wind and tide over time. That is over time your two coordinates vary depending on a third (or if you like, more).

If you have gone down with your boat the Coast Guard would have no hope finding you (albeit you may be dead) if cannot track underwater (sonar, current forecasts etc.)

It took seventy years to find the Titanic even though they had the longitude and latitude. They still looking for that Malaysian airline that went down in the (they think) Indian Ocean.

[zenoahphobic]

So I would not only give the Coast Guard the two L but my ground speed, my surface speed and direction. And a calculation if at all possible (expressed as longitude and latitude) where I would be in say one hour if that might be the time for them to get to me.

[TownsendsFJR1300]

While on this off shoot of the original topic, question;

With the GPS tied into the radio (to put out your location when the emergency button is pressed)

-MMSI, https://en.wikipedia.org/wiki/Mariti...rvice_Identity (NOT EPIRB)


does your say drifting location follow that ORIGINAL signal or ONLY update as you transmit to the CG?

[boscoe99]

CG only wants to know my last known location in latitude and longitude. They have all of the resources to determine wind and current velocities and direction.

Actually, that is the information that an EPIRB will be sending to the satellite in the sky. I don't even have to talk to anyone at all.

And when the CG is within a large number of miles of my location all they will have to do is to home in on 121.5 to fly right over the top of me.

[zenoahphobic]

121 has been replaced by 433 for marine, the latter for aircraft only. Though USA would be leaders in this. 433 more accurate to pin point we were told to throw away old 121 in Australia.

BTW if searching by aircraft the area able to viewed is far greater than by sea.
A plane cannot rescue a boat. Only occupants if suitable by helicopter.