Engine re-build - Detroit - Desicion made - Start 03 Nov 2011

[Divemaster1]

Well, not much progress to show today (hence no pictures), as it has been a day with mixed success... with a fair bit of frustration (amongst answering e-mails etc.). Hoping for a better day tomorrow, but have managed to.
1) Disconnect all cooling system hoses to and from the return water manifold
2) Disconnected Gear, throttle, Stop solenoid brackets and moved the units aside
3) Removed the return water manifold...(that is the return cooling water which circulates through the cylinder head)
4) Loosened all but two nuts for exhaust manifold (two will have to be removed by force)
5) Cleaned access around openings in manifold etc.
6) Removed Rocker Cover and started to loosen the fuel rack
7) Oil completely drained

Tomorrow will be removing exhaust manifold (after cutting nuts), then onto the cylinder head and filter brackets etc., around oilpan .... in prep for removing...

 

[Divemaster1]

So, an update from "Cheap Cylinder Repairs Company" .....

A frustrating day yesterday ... bruised knucles, stuck bolts etc., but quite successful...

Removed (after some swearing) the water outlet manifold and exhaust manifold.

Then we were on to the injector rack tube and the head (110Kg) itself...

Funnily enouth, the fuel rack turned out to be a pain, whilst the cylinder head bolts got removed relatively simple, but how were we to lift the head ??

Got the notion of some bars across, and lifting like a windlass.....

[

Which worked surprisingly well .... that is once we got the right tension on each side, so the head did not wedge in.... then controlling the swing as the head righted itself from its 45 degree angle (hence low bars rather than lifting frame). Here suspended right under the bars ...

Then some convincing between me and a mate that we were still young and used to bench press 90 Kg +, we decided to "bend zee knees und lift" the bars, shifting the head up a couple of feet, then step sideways and lower onto blocks .... well, it worked surprisingly well and within seconds we had the cylinder head safely resting on two blocks...

With clear access to the cylinders, piston and liners...

.... and to prove I was not too wrong, the offending piston, which is cracked at the top of this picture ...

Now down below to see what kind of access I have to the crankshaft etc, to loosen the piston from below and to push the piston (and liner) out in one.... wish me luck !!!

 

[LittleShip]

Hi Alf,

I dont know why but I have only just seen this thread

When you have that engine room all cleaned up and back together I'll come for a beer

Good luck with the project and keep the photos coming.

All the best

Little Ship and her crew.

 

[[2068]]

Swmbo thinks I'm mad.
Long list of housie things to get through, and instead I am spending my very limited free time on the internet, looking at pictures of poorly engines

 

[tinkicker0]

Looks like mechanical damage rather than fuelling.

Ring broken on assembly, piston pin circlip adrift (not likely by position of damage), hydraulic lock at some time in the past or mechanical damge due to foreign object being swallowed.

All could cause that. I'd favour a broken second piston ring by whoever put the piston in. Unable to be definitive without seeing the piston out.

 

[MapisM]

wish me luck !!!

Good luck!
Impressive job indeed, I guess you must be a pro mechanic/engineer, aren't you? That's not the average boater DIY job, surely!

If you don't mind a slight drift, am I right in understanding from the pic below that your boat has a round bilge? I would have thought that she had a hard chine hull...

 

[Divemaster1]

Good luck!
Impressive job indeed, I guess you must be a pro mechanic/engineer, aren't you? That's not the average boater DIY job, surely!

If you don't mind a slight drift, am I right in understanding from the pic below that your boat has a round bilge? I would have thought that she had a hard chine hull...

Thanks !!! ... Definetly DIY ....Business management and economics ... now doing integrated 1, 2 & 3D Engineering Information Management in large complex organisations which are asset intensive (Oil & Gas, Infrastructure etc.).... So a DIY job because I am interested and want to do this myself ... and have some mechanical skills... (perhaps I have chosen the wrong career path... )

Hull is definetly hard chine and not round bilge..

 

[MapisM]

Hull is definetly hard chine and not round bilge..

Blimey, it must be thick as a brick along the chines, judging by the previous pic...!

Congrats for the mech skills. I also built up some many years ago, on car engines, but never had the wish nor the time to put them in practice also on big diesels. Well, not to such extent, that is!

 

[ccscott49]

Looks like mechanical damage rather than fuelling.

Ring broken on assembly, piston pin circlip adrift (not likely by position of damage), hydraulic lock at some time in the past or mechanical damge due to foreign object being swallowed.

All could cause that. I'd favour a broken second piston ring by whoever put the piston in. Unable to be definitive without seeing the piston out.

I agree with your diagnosis, if it was an ingested foriegn object, it would have probably taken out the turbo and supercharger, before getting that far. If you could have got at the airbox, you can see the piston rings as they pass the induction ports. Just as an aside, you can judge the wear (on military engines anyway) by inspecting the rings through the airbox, they have a groove etched in them, that when it disappears, the rings need changing. Clever eh!

 

[vas]

well done Alf!

are you only going to replace liners/piston on the offending cylinder, or on all?
Eagerly waiting for piston pics.

cheers

V.

 

[icepatrol]

Alf,
james here, you remember i had to have a complete rebuild of one of my detroits.
i read with interest your comments and was wondering how you will be approaching the problem of lifting out....
even after taking a good part of the "extras" out you will still be left with a massive weight problem, i am presumming your taking out the whole engine.
mine had to be in situ, even with the saloon floors up, seating removed etc etc you cannot get anything strong enough to reach in then have the height to lift up wards.
we tried with one of those cranes on the back of a container lorry. the reach was fine but not enough height for the crane.
i had heard of a company near newcastle that wanted to remove my flybridge and take the saloon roof off.. ha !!!!!
we only just managed to get the gearbox out with the said crane. the engine was much further back so couldnt be lifted.
as you might know were well done now, but at the time...........phew.
the very best of luck.......let us know, if you get the time. lol.
james.

 

[vas]

Alf,
james here, you remember i had to have a complete rebuild of one of my detroits.
i read with interest your comments and was wondering how you will be approaching the problem of lifting out....
even after taking a good part of the "extras" out you will still be left with a massive weight problem, i am presumming your taking out the whole engine.
mine had to be in situ, even with the saloon floors up, seating removed etc etc you cannot get anything strong enough to reach in then have the height to lift up wards.

james.

I think the whole idea is that it's going to be done in situ. Only liner(s) and piston(s) to be changed, no need for any machining work to be done

following with great interest!

V.

 

[Divemaster1]

Bingo !!!

I think the whole idea is that it's going to be done in situ. Only liner(s) and piston(s) to be changed, no need for any machining work to be done

following with great interest!
V.

Got to have some luck !!! Slanting engien block means odd shape oil pan, so in order to drop it, you have to loosen bolts from the inside. To get inside, you have access hatches in the oilpan. Shere luck will have it that I coud access the clamshell bearings for the two first pistons by just opening this hatch.....

So near the bottom of the stroke, I could access the clamshell bearing bolts and remove these... short knock on the joint loosened the bottom end..... and the rod, in principle was free from the crankshaft....

Then slow rotate the engine with bar, pushed the piston and liner up the way.... (problem was retaining the other five).

For then (after some hard work pulling....) to remove liner followed by piston (more strong words...) ... so here the pieces are out....

Now enjoying one of Scotland's finer liquids contemplating parts ordering and putting the engine back into working order again ...

 

[JKay]

pissed and broke !!!

Epic tale Good Luck with the rest

 

[Divemaster1]

Other cylinders ...

well done Alf!

are you only going to replace liners/piston on the offending cylinder, or on all?
Eagerly waiting for piston pics.

cheers

V.

Having measured, all the other cylinders, pistons, liners and rings are "as new" from a factory tolerance perspective (got workshop manual), so nothing to gain from replacing more than the one, plus all seals of course...

 

[benjenbav]

Great stuff, Alf. And at least we now all know where Santa spends his spare time:

in the engine room of your boat.

 

[Divemaster1]

Great stuff, Alf. And at least we now all know where Santa spends his spare time:........ in the engine room of your boat.

Alf is Norse derrived from Alv, which equals to English Elf ... So gaining the shape of Santa, grey hair and beard... I am really "............. in training" ... but please don't tell anyone !!!

 

[vas]

interesting,

any idea why that bit of the piston went missing?
I guess the marks on the piston are from this bit of metal jumping and being squashed around.
I guess you have to check carefully the blades of the exhaust part of the turbocharger for damage.

So will have it running in 2 days I guess (spares should be easily available and affordable, right?)

cheers

V.

PS. off to Athens for the 180nm delivery trip on Tue, wish me luck

 

[Divemaster1]

interesting,

any idea why that bit of the piston went missing?
I guess the marks on the piston are from this bit of metal jumping and being squashed around.
I guess you have to check carefully the blades of the exhaust part of the turbocharger for damage.

So will have it running in 2 days I guess (spares should be easily available and affordable, right?).........

Nope, not yet .... and may be.... and presume ejected through exhaust in pieces (no damage to valves or turbo blades....

Full new Piston, rod, rings, bearings and liner should be about £250 .... but Piston skirt, rod and bearings are nearly as new, so may get away with piston crown and liner .... will need to assess this a bit closer over the next day or two...

Took me close to four days to remove, so will take at least the same to put together again.... and I need to device a gentler way of lowering the cylinder head down again onto some guide studs ... A frames and chain blocks spring to mind ...

 

[burgundyben]

Full new Piston, rod, rings, bearings and liner should be about £250 .... but Piston skirt, rod and bearings are nearly as new, so may get away with piston crown and liner .... will need to assess this a bit closer over the next day or two...
...

So piston crown and skirt are separate parts? Unusual.