G 400 engine health check

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jogranthamx
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Hi Guys                         

I’ve recently purchased a 2001 imported G 400 and I was wondering if anybody could offer any advice on how to test the health of the engine. I’ve looked in to putting it on the Mercedes fault diagnosis equipment to read any faults and I’m going to take it to a rolling road to check the performance etc. Is there any other things I could test before making improvements. 

 

jdring
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Re: G 400 engine health check

Sounds like an interesting car.

You will get loads of information and history from a proper STAR report.  I assume you didn't mean just checking ECU faults etc with an OBD reader!

Rolling road will get a power reading and brake efficiency.

A mechanic doing an oil change will give you the best opinion - state of the oil, filter, drips and leaks.

Simple pressure test on the radiator/coolant system (tell me about it!)

Maybe compression test the cylinders (valves, rings condition and wear).

Emissions test - you get those with a MOT if they actually do it.... might indicate tuning needed etc.

Got a picture of the beast?

jogranthamx
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Re: G 400 engine health check

Sorry mate can’t work out how to attach an image I’m new to the site trying to find my feet thanks for the advice. 

 When I purchased the vehicle I knew  it had a good service history till  2016 it has a few weeps of oil not leeks it has a small weep from the coolant as well everything drives and sounds correct. I just want to try to improve the car and give the engine a little love. Just don’t know we’re to start first I’ve serviced it and Replaced the steering damper this has made a massive improvement to it’s drive ability. It’s done a lot of miles and dances the oil cap around when it undone and left running.  But I did know what I was buying I wanted a car I could improve  and I like the fact that everybody else stays away from the V8 diesel I love it

jogranthamx
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Re: G 400 engine health check

Sorry mate can’t work out how to attach an image I’m new to the site trying to find my feet thanks for the advice. 

 When I purchased the vehicle I knew  it had a good service history till  2016 it has a few weeps of oil not leeks it has a small weep from the coolant as well everything drives and sounds correct. I just want to try to improve the car and give the engine a little love. Just don’t know we’re to start first I’ve serviced it and Replaced the steering damper this has made a massive improvement to it’s drive ability. It’s done a lot of miles and dances the oil cap around when it undone and left running.  But I did know what I was buying I wanted a car I could improve  and I like the fact that everybody else stays away from the V8 diesel I love it

jdring
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Re: G 400 engine health check

lol.  The double post on this site is a natural hazard!   There have been threads about changing the website, but there is so much blog information on here that moving to something more uptodate is a bit of an undertaking.  Add pics is another chore and adding videos is (I think) impossible, which is a shame (can just post the link to a uploaded youtube clip instead).

I have a V6 diesel E350 and its great.  Figured a V8 diesel in a heavier G would be pretty nice actually.

Good call on the steering damper - did my 230GE a couple of weeks back too, but then somethin in that engine blew after I fixed a coolant leak.  I think it is big end :(    Will find out today.

As a diesel, maybe the best returns would be on the injectors?  Give it an injector treatment.  Better get more mechanical advice from others on here because I stick to understanding how things work and do not have the skills, tools, time or space to do it myself anymore.

 

 

Pistonhead
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Re: G 400 engine health check

Generally on Diesels' it is crucial to learn of its service history; a dirty harbors lots of potential problems such as clogged EGR valves and it tract of piping. The journey types the vehicle has endured - Motorway driving is good news but urban driving with lots of stop/starts is bad news for blocked or blocking DPF (Diesel Particulate Filters) and costly to put right.

Starter Motor performance is important, and to do starter motor on the V8 Diesel is eye watering - get a quote from a dealer  and see for your self. I have had do one on a GL with a V8 Diesel, same twin turbo and similar chassis frame. Undoing the starter is not a problem but once undone, how to get off is challenge. I believe the book time is between 5 - 8 hours. Speaking to one German dealer close to the Factory family of repairs they told me that they had to remove the front off to slide the starter motor out. I do not know the general life of a stater on a V8 but in the early W463 a stater failure was common circa 70-90,000 miles.

Aside form high maintenance it is a fantastic vehicle.

Good Luck.

jogranthamx
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Re: G 400 engine health check

Thanks for the advice I really appreciate it what I am learning from all of my chats and discussions is that my car has quite a complicated engine in quite a confined space for maintenance and improvement are going to be challenging. But if it was easy everybody would be doing it so I’m looking forward to the challenge of getting my car as close to perfect as I can.