Wrong Fuel Accumulator

[Mick74]

Hi All,

Finally got a W116 6.9 (34 years waiting, since I read about one when I was 10 years old).

I purchased a new fuel accumulator to tackle a hot starting issue and got the one pictured with two threaded points, part no. 0438170004, as that's what was supposed to be compatible with my 1979 model. (Repeated internet checks, and they were wrong. Go figure)

Turns out, my car is fitted with part no. 0438170017, which is identical, but just has the centre threaded point and not the rhs one.

I was going to return it (will cost €35-€40 in postage to send back and get the other one) but I then thought that I might get away with capping the rhs point, and my local mechanic thinks this might work.

Any thoughts before I run petrol through this?

Mike

[ptashek]

The 6.9 is a unique beast, I'd rather go with the proper part given it's on a critical path...
So you're the new lucky owner of this piece: https://themarket.co.uk/listings/mercedes-benz/450sel-69/ba7cf075-21f8-4940-a933-9d724e6ed9e3

Have you had a chance to inspect it in full yet?

[s class]

Despite what internet listings might tell you, generally the early Kjet cars say 76 to 78 use the double port accumulator, while the later cars say 79 to 80 use the single port accumulator.  The 6.9 is not special in this regard.  This changeover was across the 116 and 107 range at the time.  Unkess you are super concerned with accuracy, you can use the double port unit, and just cap the unused port.  We've done that several times in our shop when I didn't have a single port unit on hand and the customer didn't want additional lead time.

[Mick74]

  Unkess you are super concerned with accuracy, you can use the double port unit, and just cap the unused port.  We've done that several times in our shop when I didn't have a single port unit on hand and the customer didn't want additional lead time.
[/quote]

Thanks for that. I am caught for time in that I'm going on a run this weekend and I don't switch the car off, if I can avoid it, because it cranks for up to 6-7 seconds when hot, which seems a painfully long time. I'll cap it and fit it and let you know what happens.

So you're the new lucky owner of this piece: https://themarket.co.uk/listings/mercedes-benz/450sel-69/ba7cf075-21f8-4940-a933-9d724e6ed9e3
I am indeed! Well spotted. I've just posted a newbie post about it, but it was honestly advertised. I haven't done serious poking about, but there doesn't seem to be anything terminal yet. No doubt something will rear it's head, but I've budgeted up to €12k over the next few years, if necessary, to keep it right. It cost me €18,200 in total by the time it came home, so €30k overall for a well sorted, if not show winning 6.9 seems ok. If I'm lucky and it comes in less than that, well and good.
We'll probably meet at some stage, as while I'm in Galway, my sister lives in Portlaoise and has a W123, so we'll be going to alot of shows around the country.
Mike

Have you had a chance to inspect it in full yet?

[Mick74]

Seems that I've managed to delete my emotional essay re new 116 ownership. 
I'll have to try that again.

[daantjie]

I run the accumulator ending in "004" on my 6.9, the same part# you have in your picture, and it works like a charm on mine.  I have 1977 US spec model.

[Mick74]

I'll just have to be more thorough when ordering parts and not trust the internet configurators. It is a critical system, as ptashek says, and I'd prefer the exact part, but time is an issue.
We live and learn.

[ptashek]

Despite what internet listings might tell you, generally the early Kjet cars say 76 to 78 use the double port accumulator, while the later cars say 79 to 80 use the single port accumulator.  The 6.9 is not special in this regard.  This changeover was across the 116 and 107 range at the time.  Unkess you are super concerned with accuracy, you can use the double port unit, and just cap the unused port.  We've done that several times in our shop when I didn't have a single port unit on hand and the customer didn't want additional lead time.

Learning something new every day. Thanks

[ptashek]

I've budgeted up to €12k over the next few years, if necessary, to keep it right. It cost me €18,200 in total by the time it came home, so €30k overall for a well sorted, if not show winning 6.9 seems ok. If I'm lucky and it comes in less than that, well and good.
[/quote]

Sounds like a reasonable plan.
It's great to see another W116 on Irish roads. I'm sure we'll run into each other at one show or another