omega2
Well-Known Member
I await the outcome with interest, hope it is positive. Our engines are generally clean, as they are "out" there, not to be ignored. LOL
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Detroit Diesel. Non Starter
- Thread starter syd
- Start date
I await the outcome with interest, hope it is positive. Our engines are generally clean, as they are "out" there, not to be ignored. LOL
Divemaster1
Well-Known Member
Sorry Syd,
Think you may need to re-think...
Suspect that you acctually have a 4 valve head at your rating !!
This is a 4 valve head and the "bridge" is being pushed by the rocker and thus pushes two valves ... and there are two valve rockers for each cylinder ... plus the injector rocker... but you only check clearance at one valve for each rocker...
edit: you see the 4 valves better here... with the "bridge" crossing over the two valves in situ and injector removed...
However, if you have a two valve head, you are way out of tune !! The two valve head exhaust valve clearing should be 0.012" !!!!
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syd
Well-Known Member
Wow. I'm going to have to have another look to be certain. I'm sure there was only adjustment for two valves per head, just like the old side cam engines. Looking closely at your picture I can see how I might have missed the other two, but I'm sure/not sure now, there were only two. Back to the boat.
Regards Syd
Regards Syd
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Divemaster1
Well-Known Member
Syd, there are three rockers per cylinder ... ( 2x valve & 1x injector)
Adjustments (and checks) are only 1x per rocker (on 4 valve engines 1x adjustment does 2x valves)... and adjustment is at the push rod end, where there is a locking nut and an adjustment nut (a bit awkward to get to the lower nut, but no special tools required ... see illustration) ... do not try to adjust the nut & bolt(s) on the "valve bridge" .....
Hope this helps... and can be on phone for you if you want to have someone to talk to when you go through the work ...
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syd
Well-Known Member
Went to boat yesterday. First job remove rocker lid.. Low and behold FOUR valves per head !! How did I miss that ?? Thanks Alf. I put my hot air gun on low and left it feeding air intake for about fifteen minutes. Pushed the starter... Splutter splutter Vrooooom.. Off she went. Big smiles again..Thanks everyone for all your help. I'm having Arista lifted out on the 30th for antifoul and anodes, after I've checked all the appropriate bits for signs of wear I'm going to take her out for a good long blast, clear the cobwebbs. the re check the settings. Looking forward to that. I'm gradually getting more familiar with the workings and characteristics of the DD's. Its a big learning curve.
Cheers All
Syd
Cheers All
Syd
Bertramdriver
Well-Known Member
Thanks Syd, between you and Alf I've learned more about my DD's in the past month than I have in the past 10 years. At least i will be able to keep an eye on my mechanic now. More strength to your arm and I wish I could crew for the test run (unfortunately i'll be somewhere in the Corinthian Sea). Remember max 2300, cruise at 1750 and sing along to the DD's.
Hope to keep in contact
Jon
Hope to keep in contact
Jon
Divemaster1
Well-Known Member
Good news Syd !! .... it is obvious, ..... when you know where tho look that is. Probably obscured by the rocker, and your focus on the valve where you checked the clearance
The slow starting bit if it persists into spring & summer could be a concern as it could be low compression (compression test will reveal this)... hoewer, it is good to hear that the KIS principle still works, bet she kicked in on a couple cylinders which would have helped cranking speed, then ran for a short while on something that sounded like four or five before all six kicked in ...... Smoking a bit was she ??
syd
Well-Known Member
I would love to have my old girl moored out there. The air con still works but we don't get to use it very often in UK.. All the best.
Syd
Syd
syd
Well-Known Member
Exactly that Alf. Chugged for a while, progessed into spluttering as other cylinders kicked in then away she went in great plooms of smoke. Cleared within a minute or two. Well chuffed but will keep a close eye on it.
Syd
Syd
syd
Well-Known Member
Thanks Syd, between you and Alf I've learned more about my DD's in the past month than I have in the past 10 years. At least i will be able to keep an eye on my mechanic now. More strength to your arm and I wish I could crew for the test run (unfortunately i'll be somewhere in the Corinthian Sea). Remember max 2300, cruise at 1750 and sing along to the DD's.
Hope to keep in contact.
Cheers Jon.
I would love to have my old girl moored out there. The air con still works but we don't get to use it very often in UK.. All the best.
Syd
omega2
Well-Known Member
There you go! nothing difficult about it was there. ? If it ain't broke don't fix it.
Bertramdriver
Well-Known Member
I remind you Syd that the cruise air aircon is a reverse cycle system. Switch it on and bask in the lightly scented (aire de Deisel) warm air. Last time I tried to run my aircon off shore power it blew up the main transformer in the harbour. I've never moved so quickly to unhook my shorepower line before anybody noticed it was me.
Divemaster1
Well-Known Member
Bertramdriver
Well-Known Member
10 years and 1500 miles probably grant immunity!
vas
Well-Known Member
just tell us which marina it was, and next wed when I'm in Athens I'll go and spit it out
as if they'd give a damn...
Syd/Alf,
if syd tries to start the engine after a couple of days in similar conditions, would he expect it to fail again and resort to using the heatgun?
cheers
V.
Bertramdriver
Well-Known Member
The harbour was Mikro Limino, one up from Zea Marina and home of the Royal Hellenic Yacht Club.
if Syd needs hot engines he only has to wait to July. It gets to 40+ then, water temp in the marina 25.
Come to think of it most of the Royal Hellenics have probably sold their boats by now so you might get a berth.
if Syd needs hot engines he only has to wait to July. It gets to 40+ then, water temp in the marina 25.
Come to think of it most of the Royal Hellenics have probably sold their boats by now so you might get a berth.
sailorman
Well-Known Member
having read another DD thread, are you serious that a re-build is required @ 1,000 hrs. That could be 1 a year or more on commercial use
Bertramdriver
Well-Known Member
One for Divemaster1 I think
Divemaster1
Well-Known Member
Hot-Rod Detroit Diesels ... ie' where you push the HP limits on these long stroke engines where tolerances of overheating etc., are getting closer to the limits..... and all about the configuration of the engines.... and particularly where engine is overloaded by overpropping etc.
As an example, the straight six 71 (7 Litres) series were delivered in anything between 180 and up to 485 hp ... that is a huge range for the same base engine ... the latter were never delivered as a commercially rating !! the same goes for the whole series of Detroit's... This engine did very well up to about 410 Hp ... and after that re-builds became more frequent ... and the 485 Hp one, if you ran her hard .... that is 200 RPM under max (2300).... you could risk a re-build after 1000 - 1500 hrs ... throw in neglect by not doing regular oil change etc., and you'll shorten this...
The commercially rated ones, such as the ones used in the Tyne Class lifeboat, offshore cranes, pumps, tugboats, trucks, workboats, buses, etc., will outlast most anything... It is not un-common to see a commercially rated DD with anything between 20 - 40,000 hours on the clock.... and when treated with due respect, engines like the 6/71 in-line @ about 200 hp, will never have seen anything else but filter & oil change, plus valve and injector adjustments during this period...
I am trying to keep prospective owners informed and have a realistic perspective, and cost of ownership of any highly stressed engine tend to mean "Big Bill" will come knocking every now & then ... Having said that, all these 2 stroke lumbering, screaming, singing, spluttering, smooth running DD's are re-buildable from virtually any (non block) failures .... unlike a lot of modern diesels.... and they will run at less than ideal conditons .... as an example, I ran one of my 6/71's on five cylinders last season, by simply restricting fuel to the damaged cylinder to what was needed for lube/cooling only .... how many modern engines allows for that as a "get home feature" ??
As I was boating around the North Sea, I wanted engines that allow me to damage them, to save life rather than the other way around ....
[rant on]... so I do not accept the current "safe mode" of some manufacturers, where focus is on protecting engines at the potential cost of the people on the vessel... Basically, I want an override where I as a skipper can have a choice of wrecking the engine(s) to hold off, or avoid other navigation/weather dangers to preserve life .... a software techie., should not be allowed to make that desicion for me!!! ... [rant over] ... my DD's allow me to do that .... and will forgive me when I re-build them...
sailorman
Well-Known Member
Thank you very enlightening.
as with all engines do not over stress them as with many light weight modern diesels with turbos