Menu toggle

pressure relief valve

S

stevejohnson

New member
My 89 turbo is in garage having a new head gasket. While the engine is apart the garage have suggested fitting a 'pressure relief valve' (part no. 94410723901) to cure its rough running on start up when cold - cost 171+VAT.
The rough running dosn't really bother me that much as it only lasts a minute or so. My question is whether there are any other intrisic benefits? The garage were a bit vague, they weren't even sure if it was an original part or a modification (the chief mechanic is on hols and they want me to make decision by the time he gets back so they can order the part in time)
Any one have any knowledge/experience of this?
 
Just looked it up in the PET and it seems to fit towards the rear of the cylinder head and looks like a part you can fit anytime without having to remove the cylinder head, although you'd have to remove the rocker cover. Other than that I've never heard of it before. I'd be inclined to have it done if rough running on start up is a symptom of it's failure. It's never good to have a rough running engine in my view. These things are designed to run smoothly.
 
Are they suggesting you fit one or you replace a failed one that was there as standard? I haven't heard of it either.
 
I got the impresion that it is not a replacement part but some sort of modification - although the part is a genuine porsche part.
 
If it's a modification then it's being suggested to mask a failing elsewhere, and one that isn't commonly known on here as a known 944T weakness it would seem. On that basis I'd suggest correcting the root cause rather than masking the symptom.

Isn't the rough running for a short period just a symptom of the head gasket failure I presume you had? Quite often when the HG fails you get water in one cylinder which condenses as the engine cools and the car will run on 3 when you start it until it has been sufficiently cleared out.

How good / experienced is the garage (especially with the 944)?
 
ORIGINAL: Fen

.....Isn't the rough running for a short period just a symptom of the head gasket failure I presume you had? Quite often when the HG fails you get water in one cylinder which condenses as the engine cools and the car will run on 3 when you start it until it has been sufficiently cleared out.

How good / experienced is the garage (especially with the 944)?
Click to expand...

Ditto.

The car obviously ran smoothly previously without a pressure relief valve so I see no advantage in fitting one now.
 
Thanks guys. When they originally diagnosed the gasket failure they told me that explained the roughness on start up. The garage is La Rose in Kemsing in Kent. They have served me very well through many years and porsches. But you have confirmed my instincts. I think I will see how she runs after the gasket has been fixed and I suspect you've helped me save 171 +VAT. So many thanks again
Steve
 
You must log in or register to reply here.

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Porsche
Lockton
Pirelli
Officially approved
Oracle Finance
WEX Esso
Collecting Cars
Back
Top