Mercruiser 1.7 Turbo

michaelross2000 · 16 May 2007, 16:52

I have a 18' Regal 1800 with Mercruiser 1.7 DTI Engine (2003). Bought her last year and had a great season. However after 1 week in the water this year the turbo has gone. Wastegate siezed and some "bit" cos I aint a mechanical guy, has gone into the turbo and broke it.:-(

I am trying to source a recon turbo for this engine with absolutley no success at all. Any one know what turbo this is in the UK. I have been told IZUZU, MITSIBUSHI & OPEL so far but I have no Idea what to do. Would prefer not to have to replace for new if possible.

Thanks for any help.

Mick

Nos4r2 · 16 May 2007, 17:01

Take the turbo into a Vauxhall dealer and see if they can match it. The 1.7 mercruiser lump is the Isuzu diesel from the 1.7 Vauxhalls.

Ask a marine engineer first though before actually paying for one-the 1.7 td Vauxhall/Isuzu engine doesn't chuck out anywhere near 120hp and I suspect a fair proportion of that is extra turbo pressure.

nik · 16 May 2007, 18:45

I had exactly the same problem. Luckily being done under warranty.
If it had not been, I would have looked at getting it rebuilt, at a guess, £300-£400.

mikesyam · 16 May 2007, 19:00

Look in your local auto trader in the services section, there are loads of turbo reconditioners in there, I used turbo technics and they were great and cheap.

alt · 16 May 2007, 19:01

There was a (working) turbo on ebay not so long ago, went for £170 in the end. I was going to bid on it as a spare when I had a 1.7 (Now sold)

Register with http://groups.yahoo.com/group/cummin...ser_120hp_DTI/ they're an owners group. While you'll get excellent info here on rib.net (I certainly have - I owe half the place a pint!) you might get some helpful info there too

What happened you is a very common problem. Some people reckon spraying some Mouse Milk (Do a google search, not actual milk of a mouse!) into the wastegate auctuator (sp?) can help keep the bearing that seizes, free. Bit late now, but you'll know for again

nik · 16 May 2007, 22:49

Hello Alt,
I have been trying to get to the bottom of this, it seems a common fault.
These engines work ok in cars but not so well in boats, one difference is the increased horsepower in the boat version, is it a different turbo?

It has also been suggested that corrosion could lead to the wastegate valve sticking open and lubrication could help it. But how do you do that when it is all encased in that really, really expensive heat resisting shroud.

You mention a bearing that siezes, can you tell me which one? I had a look at my turbo after the failure and it span freely. I still have not had a post mortem on the possible cause.

One thing that I have been told is that when these engines are used commercially, they last a lot longer. That could be down to regular use, or less use at maximum rpm.

Sorry to bombard you with these questions, but I would really like to know anything you know about these engine problems.

Nick

alt · 16 May 2007, 23:33

No problem,
I am no expert, but this is my feeling:

The bearing that seizes is inside the auctuator. Feel back to the turbo, now see the arm going into the circular thing? Thats the wastegate arm. The circular thing is the auctuator that opens the wastegate when it reaches a certain pressure (17PSI on the 1.7 if I recall, could be wrong)

The problem is that the bearing insize that auctuator seizes, hence the arm does not open, hence turbo failure and possible engine damage due to over-boosting.

I used to spray WD40 into the auctuator every so often. This seemed to lube the bearing and keep it free from corrosion, however Milk Mouse is recommended as it's a "High temp lube"

I used my boat on fresh water, however it is suspected that the salt air contributes to the bearing seizing.

I think that when you say the commercial engines last longer, it's because theyre being used ie. the Wastegate is working a bit. Think of it like this, if you don't move your car for a long time the hand-brake can get sticky. Same principle for your wastegate

In a perfect world the wastegate would never need to be activated. That is why it is recommended to get a low pitch prop so that your engine never has to run under much load. I changed my prop so that the engine could achieve 4800RPM. Of course I never opened it up fully, but by knowing that the engine CAN reach that RPM, I know it is not being over-loaded when running at cruise RPM

alt · 16 May 2007, 23:35

Here is a picture taken from another site. You can see the auctuator arm and the auctuator on the right

Biggles · 16 May 2007, 23:49

Is that bit of kit for real. Looks like something out of a Back to the Future movie.

I've got a turbo on the car and it looks like an ancient large sea snail fossil. certainly nothing like that. And that doesn't look very marine proof.

nik · 17 May 2007, 09:32

I have just spoken to my repairers, boat nearly ready, there seems to be no other damage to the turbo. I have been told that the wastegate has siezed on the "hot" end of the linkage (circled).

I am purely guessing here. Could it be that if the engine is running at full power, the turbo gets hotter, therefore leading to premature bearing siezure of the wastegate valve?

Nick.

alt · 17 May 2007, 10:05

I'd put it down to the sea air/water but that's just me!

jwalker · 17 May 2007, 11:28

It might be worth reaming that bearing out a tad to prevent the same thing happening again. I've seen some vehicles where they are a quite slack. I guess they must leak a little then but the small amount of exhaust will soon be drawn back into the engine and consumed.

I suppose as a service you could unclip the rod, give the bearing a squirt of oil and work the lever a bit to ensure it's kept free.

Nos4r2 · 17 May 2007, 12:08

Not sure I'd want to go oiling something that's hidden behind a heatshield. The shield implies it's going to get hot-maybe enough to set fire to the oil.

Maybe teflon spray would be a better idea.

alt · 17 May 2007, 12:16

Again i've heard good reports about Milk Mouse but don't know where in the UK (Or Ireland) that sells it. I contacted the manuf. in the USA and they said they'd ship it world wide

jwalker · 17 May 2007, 12:43

Quote:

Originally Posted by Nos4r2

Not sure I'd want to go oiling something that's hidden behind a heatshield. The shield implies it's going to get hot-maybe enough to set fire to the oil.

Maybe teflon spray would be a better idea.

It's just a wee squirt down a bearing, Nos4.

Nos4r2 · 17 May 2007, 12:55

Yeah but anything you put down there's going to burn off PDQ anyway-that's why I suggested teflon spray.