Breaking All the Rules ...

[Nauticatarcher]

Are you sure white smoke is smoke not steam, is there good waterflow through exhaust check mixing elbow isn't blocked

[homeless]

Definitely not steam. White smoke was from cold start up to long hot running, and left a fuel residue on the water, so definitely diesel fog. There is a lot of raw water output from the exhaust, and both the fresh water and oil heat exchangers have been cleaned out recently, and engine is not running hot or losing fresh water..

7 days ago in Gladstone I pumped 12 litres out of the engine sump and replaced with 6 litres of new oil. Today I again pumped 12 litres out of the engine sump and replaced with 6 litres of new oil. The extra 6 litres I pumped out today can only be diesel leaking into the engine from injectors (pressure tested OK yesterday, so unlikely), lift pump diaphram, or high pressure pump shaft seal. Today I bypassed the lift pump with a hose directly from the Racor fuel filter to the engine fuel filter to remove one more potential source of diesel.

After changing the oil again today the white smoke was greatly reduced, so I suspect high diesel content in the oil was a significant contributor to the smoke and this also explains the drop in oil pressure seen on the gauge. Will need to watch the oil level to see if it rises again indicating diesel is still leaking into the engine, as in addition to white smoke the reduced viscosity will increase engine wear.

Today I also found a machine shop who can fabricate my mainsail batten-car connector bracket. Should have it back tomorrow, then head North again.

[mrm]

Originally Posted by homeless

Definitely not steam. White smoke was from cold start up to long hot running, and left a fuel residue on the water, so definitely diesel fog.

7 days ago in Gladstone I pumped 12 litres out of the engine sump and replaced with 6 litres of new oil. Today I again pumped 12 litres out of the engine sump and replaced with 6 litres of new oil.

The extra 6 litres I pumped out today can only be diesel leaking into the engine from injectors (pressure tested OK yesterday, so unlikely), lift pump diaphram, or high pressure pump shaft seal.

My thoughts on that: your injectors and pump may be fine and just doing their job, but you may have no or marginal compression in one cylinder and unburned fuel goes both to the exhaust and leaks down to crankcase (maybe broken rings?).

Although.. 6 liters in 7 days seems excessive.

How was the compression check?

[homeless]

When bleeding the high pressure lines to the injectors one at a time the impact of one cylinder not firing at idle is obvious, but with all high pressure lines connected the engine starts easily, idles smoothly, runs smoothly, and puts out plenty of power up through the rev range, so the diesel mechanic decided compression on all cylinders was OK and there was no need to test.

By the time I get to Townsville I should know if the diesel leak into the engine and the white exhaust smoke are truly resolved. If not ... find another mechanic and get another opinion.

[homeless]

Now anchored at Cape Richardson on Hinchinbrook Island with the sounds of tropical birds in the trees and fish splashing around the boat. Spectacular tropical beach but I doubt I could afford the resort. Spent last night anchored at Greater Palm Island with mantas cruising the bay.

Engine is still putting out a lot of smoke, oil level is rising, and oil pressure is dropping indicating diesel is still leaking into the engine. Will rebuild the fuel pump when I get to Cairns along with a rebuild of the gearbox.

[transmitterdan]

Homeless,

You should develop a contingency plan for engine runaway. This happens when an engine is able to burn its own lube oil. An overfilled oil sump can create this condition. For example, one way is oil can be blown out a crankcase vent and sucked into the air intake but there are other ways. The only way to stop or slow a runaway engine is by blocking the air intake. A 4" air intake can create about 150 pounds of force so don't try to use your hand. Have a piece of sturdy wood or metal handy to block the air intake if she runs away. It sounds frightening but usually doesn't cause harm if stopped quickly.

The odds are this won't happen but if it does it's much less of an event if the right material is at the ready. When an engine runs away it's unlikely the transmission can be disengaged so time may be in short supply.

[Cadence]

Originally Posted by transmitterdan

Homeless,

You should develop a contingency plan for engine runaway. This happens when an engine is able to burn its own lube oil. An overfilled oil sump can create this condition. For example, one way is oil can be blown out a crankcase vent and sucked into the air intake but there are other ways. The only way to stop or slow a runaway engine is by blocking the air intake. A 4" air intake can create about 150 pounds of force so don't try to use your hand. Have a piece of sturdy wood or metal handy to block the air intake if she runs away. It sounds frightening but usually doesn't cause harm if stopped quickly.

The odds are this won't happen but if it does it's much less of an event if the right material is at the ready. When an engine runs away it's unlikely the transmission can be disengaged so time may be in short supply.

A piece from your weather gear">foul weather gear works well if you need something quick.

[homeless]

Now in Cairns playing with spanners ...

So far I have not been able to get the gearbox off the engine. I disconnected the gearbox from the prop shaft, and took 6 bolts out of a plate attaching the gearbox to the bell housing, but can't move the plate or the box, and don't really want to take the gearbox apart piece by piece while still attached to the engine. It is possible that the splines are corroded together and I just need to use a bit more force, but don't want to try that option until I have exhausted all others like hidden bolts, split rings, grub screws etc. Any ideas on what I am missing removing a Hurth gearbox from a Perkins engine ?

Since I am still getting diesel into the oil and the source is not injectors or lift pump I have now removed the injector pump, and have started asking around to see who can supply a replacement shaft seal or do a full rebuild.

[Terra Nova]

Surely you have the service manual?

[homeless]

I have the manuals for engine and gearbox, and they seem to indicate I have removed the correct bolts, but they only detail the most common methods for connecting gearbox to engine, and hint at others.

I am 99% sure that the issue is corrosion in the spline and/or drive plate, but the only way to get to the shaft with the big hammer is to first spend the better part of a day taking apart the gearbox in an impossibly small space while dropping tiny pieces in the bilges, banging my head, skinning my knuckles, and swearing creatively. To avoid that misery tomorrow my last hope is that someone here says "I had the same problem with my gearbox because I had forgotten to ..."

[barnakiel]

You may save some time&energy and some bucks too if you hang and tape a hammock of plastic ply under the repair being done. Should you drop any bolt or nut it is so much nicer not to have to dive into the bilges for it.

Also, make sure sure that it is the box that gives you trouble. Removing the thing only to find the fault is elsewhere ...

Cairns a nice spot anyways to be. Even if busy fixing an engine. Nice ocean view pools and fine friendly people in town. Good native art galleries too.

Let us know how it goes.

b.

[Cadence]

Originally Posted by homeless

I have the manuals for engine and gearbox, and they seem to indicate I have removed the correct bolts, but they only detail the most common methods for connecting gearbox to engine, and hint at others.

I am 99% sure that the issue is corrosion in the spline and/or drive plate, but the only way to get to the shaft with the big hammer is to first spend the better part of a day taking apart the gearbox in an impossibly small space while dropping tiny pieces in the bilges, banging my head, skinning my knuckles, and swearing creatively. To avoid that misery tomorrow my last hope is that someone here says "I had the same problem with my gearbox because I had forgotten to ..."

Homeless, have you tried lifting the gear box a bit. A spine won't move if alignment is not right on the money. Might even try shimming to one side or the other a few .001.

[Wanderlust]

Before going too far with disconnecting things, can you get a wedge inserted somewhere to apply constant separation force? Both sides if possible. Re-insert the bolts but with free thread exposed to allow a little fore and aft movement.

Start the engine and engage forward then reverse repeatedly. With the wedge exerting separation force, the sudden jolts may be enough to free it up. Never tried it myself but it may be worth an attempt.

[homeless]

I tried levering the gearbox apart from the bell housing using wedges, hammers, and crow bars, and can get about 10mm but no more with the force I have been using. Today I removed the engine mount bolts to allow me to slide the engine forwards to make more space and allow more leverage, and started removing everything off the outside of the block that may get in the way. Not easy sliding such a heavy engine by myself Options to try tomorrow ...

1. take the gearbox apart in place. probably won't work as I believe there are bolts into both halves of the gearbox housing from the engine side of the mounting plate.
2. support the block with wood and a jack then try to remove the bell housing and see if I can get any further than I did with the gearbox.
3. use maximum force to try to separate the gearbox or bell housing, or possibly break the drive plate connections
4. consider more destructive options like grinder or the big hammer.

[homeless]

Searching the internet it seems to be a common problem when boats flood that the gearbox input shaft gets seized in the drive plate spline, and unfortunately the solution usually seems to be to sacrifice the gearbox mounting plate to allow access to the drive plate and mounting plate bolts. Oxy cutter may be the easiest option