TZI valve clearances

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rhysaccess
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TZI valve clearances

Post by rhysaccess »

Howdy all,

While checking valve clearances on my DKZ engine, I've used the 159 specs in one of my Haynes manuals of" 0.15 - 0.25 Inlet & 0.35 - 0.45 Exhaust"

I see in a different Haynes supplement DKZ's are nominated the same as the D6a which is 0.10 - 0.15 Inlet & 0.20 - 0.30 Exhaust

(I think the Peugeot 205 GTI's used the .15/.25 & .35/.45 specs)

Given the re-shimming involved.....I'd love to get it right, once.

Anyone offer some wisdom here?

Regards,
Rhys

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saintjamesy89
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Re: TZI valve clearances

Post by saintjamesy89 »

Hi Rhys, I'm not sure if my offerings are of any use, but I thought the 159A engine was the carburetted version of the 1.9, It is what I have in my 1985 GT. I would have thought the EFI TZI had a different head and maybe even bigger/different valves and so perhaps different clearance spec's.
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rhysaccess
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Re: TZI valve clearances

Post by rhysaccess »

Hi Tom,

All input appreciated. The 159 engine (as I understood it) was just the BX19 engine. Later versions bought in a variety of numbers & letters.

I'm not a huge fan of the Haynes manuals or their potential typos- when better Citroen documentation may be available. There was nothing on my Diagbox BX folders.

I read on the internet (which I'm cautious about) of suggestions to tighten the clearances to quieten them down a bit.

In the absence of better guidance - I'll run with the conservative 0.15 - 0.25 Inlet & 0.35 - 0.45 Exhaust clearances.

Cheers,
Rhys

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Jaba
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Re: TZI valve clearances

Post by Jaba »

It is a long and fiddly job to check and then correct the clearances and they do seem to change after you have set them with a different shim and the engine has run for a bit. Looking at the Haynes it does suggest the tighter clearances for the D6A engine and your TZi engine.
Firstly though it is best to check the clearances you have now. If the inlet is somewhere between the upper and lower limits of the two different ranges given i.e. - .10 and .20 and similarly the exhaust is between .20 and .40 I personally would leave them alone.
I am sure the valve noise is unnoticeable between the upper and lower limits.

I have spent far too long in the past trying to get the clearances right, I even made up a spreadsheet to calculate the shim thickness needed and to let me see if I could use a removed shim in another position. It is a labour of love.
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rhysaccess
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Amphicar 770
Chevrolet Corvair Corsa Turbo Sport Coupe
Chevrolet Corvair Rampside
Chevroletr Corvair Monza Convertible

Re: TZI valve clearances

Post by rhysaccess »

Yes, the vagaries of chasing down some exact numbers by shimming are not new to me. If I’m to use the “standard” BX19 clearances – just three exhaust valves are a bit tight.
Rather than labour the point I’ll just adjust these shims to get .40 and move on.

My pedantic desire to have things exactly correct – is inversely proportional to the tasks I need to get done on the vehicle.

Regards,
Rhys