<VV> Fw: car running lean -adviceappreciated

[Mel Francis]

> One other item to check might be the fuel strainer on the fuel pickup in 
> the
> tank.
> Thankfully, it's an easier job on a Corvair, being located on the bottom 
> side of the tank,
> rather than up at the top.
>
> I attended a 50th anniversary event last weekend in a car that had been 
> stored for a while and
> it ran ok, but knocked from being lean, whenever I was in the higher rev 
> range on the freeway.
> Power faded to the point of not being able to keep up with the other cars 
> at 60 mph.
>
> When I got home, I noticed a bit of seepage coming from around the fuel 
> tank sender unit.
> I decided to drain the tank and investigate the seal, only to find a 
> REALLY slow-draining tank.
> Eventually, once it was empty and I opened it up, I found the strainer to 
> be almost completely blocked
> with a shiny, plastic-like deposit. Perhaps from some sort of gas 
> additive, from a previous 'servicing'.
> So, now we're replacing the strainer and adding a new tank seal.
>
> Just disconnect the rubber fuel line at the tank outlet and watch how much 
> flow you have. If it's adequate,
> the strainer is ok. But if it seems unusually slow, this could be the 
> culprit.
>
> Mel Francis
>
>
> ----- Original Message ----- 
> From: "deltainc" <deltainc at grm.net>
> To: "vv" <virtualvairs at corvair.org>
> Sent: Wednesday, October 07, 2009 2:53 PM
> Subject: Re: <VV> 828 miles this weekend - car running 
> lean -adviceappreciated
>
>
>>
>> ----- Original Message ----- 
>> From: <BobHelt at aol.com>
>> Subject: Re: <VV> 828 miles this weekend - car running lean -
>> adviceappreciated
>>
>>
>>>
>>> In a message dated 10/5/2009 6:04:33 A.M. US Mountain Standard Time,
>>> guusdehaan at me.com writes:
>>>
>>> On our  trip to Germany it was almost on lambda 14,7 all
>>> the time (mine has  a Safe Guard system with sensor in the exhaust).
>>> But on the way back  home it started running leaner and leaner (near
>>> 11). Does anyone  have an explanation what could cause this?
>>> Guus,
>>> 11 would indicate a rich mixture rather than a lean one. Are you sure 
>>> that
>>> it's 11:1?
>>
>>> In my experience and research, I have found the rubber accel pump
>>> diaphragm
>>> a problem area. The rubber hardens from natural aging and it causes the
>>> mixture to go rich. I don't know why this would happen during operation,
>>> but
>>> it  happens otherwise. The diaphragm is fairly easy to replace. I would
>>> start with  that.
>>> Regards,
>>> Bob Helt
>> *************
>> Also, the older fuel/air oxy sensors are notorious for only being 
>> "accurate"
>> when the mix is near 14.7 .....  if he is reading 11/1, with the older
>> sensors.... it really only means he is rich... not too dependable on " 
>> HOW "
>> rich.  Maybe it is really 13.7, which is not too bad.
>>
>> First thing I would check if its the older type Oxy sensor ... I would 
>> call
>> Safe Guard and ask for a short discussion, giving them the serial # on 
>> his
>> unit.
>>
>> Hmmm.  wonder if he went thru any great altitude change, or even
>> cloudy/clear conditions.
>>
>> Just a thought... ken campbell, deltawerkes
>>
>>
>>
>>
>