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Andy427
26-08-01, 02:17 PM
Hopefully someone out there can point me in the right direction to the below problem.

I have just recently finished a GD that is fitted with a Chevy 350 which until last week was running very nicely and I had just seen the speedo tick over the 200 miles mark. This is a new engine from Repower so I am still taking it easy at the moment.

Anyway after a 20 minute drive last week, the engine started to sound a bit rough and accelerating in 4th at 50mph caused quite a bit of vibration most visable from the gear shift. When I got home, the V8 burble had been replaced by pretty loud gunfire and when I turned the ignition off, the engine kept turning over for a couple of seconds before making a 'gas escaping' sound and spluttered to a stop.

I have started it up once more with similar results and the right exhaust (when viewed from the back) is smoking slightly.

I am thinking that maybe the mixture is too rich which has coked up the spark plugs but as I new to this, I thought I would ask for some opinions before I begin taking them out as they are a bit inaccessable under the exhaust manifold.

Any ideas?

Andy

robert
26-08-01, 02:28 PM
Take the rocker cover off and have a look at the lifters.

Have Fun

Andy427
26-08-01, 02:44 PM
Robert

What am I looking for? Treat me as someone who knows very little about engines.

Cheers

Andy

graham
26-08-01, 04:14 PM
Just a thought. My engine 350sbc sounded like that when test firing but possibly the hydraulic lifters have filled with oil and possibly the tappets/rockers(under the rocker valve covers) are well out of adjustment and need adjusting as per 'How to rebuild your Chevy book' OR phone REpower (Brian) to advise you after all you paid good money for this and you should seek some after sales support, I feel.

I would be interested to hear from you on how you got on.

Graham

Andy427
26-08-01, 04:52 PM
Graham

Thanks for the note - there does seem to be quite a bit of oli around under the covers but I have no idea if this is normal or not. I will give Brian and GD a ring and see what they say. You mentioned a book - is this a good one for general maintenance and if so what is the Title/Author/ISBN number?

Thanks for your help and I will let you know how I get on.

Andy

robert
26-08-01, 05:03 PM
>You mentioned a book
>- is this a good one for general maintenance and if so what is the
>Title/Author/ISBN number?

Haynes Chevrolet Engine Overhaul Manual

ISBN 1 85010 762 9

>
>Thanks for your help and I will let you know how I get on.
>
>Andy

Andy427
26-08-01, 05:44 PM
Graham

Thanks for the book details - looks like I will be needing it as I had another look at the lifters and most of them can be twisted a small amount around the central fixing. One, however, has ripped away from the bolt.

My questions are:

1. How could this happen? Is this just one of those things or have missed something?
2. Is there a chance that debris has been circulated around the engine in the oil? I have found a few fragments but not sure if all are acounted for.
3. What's the prognosis in terms of other engine damage?
4. Do you think I have any come back to the supplier?

These are mainly questions aimed at getting an idea of financial implications as, with many a cobra builder, resources are short just after registration.

Thanks in advance for your help,

Andy

robert
26-08-01, 05:56 PM
>My questions are:
>
>1. How could this happen? Is this just one of those things or have
>missed something?

It just seems to be one of those things.

>2. Is there a chance that debris has been circulated around the engine
>in the oil? I have found a few fragments but not sure if all are
>acounted for.

Yes, so I would suggest you change the oil and filter. The oil drain plug should be magnetic and pick up most of the debris.

>3. What's the prognosis in terms of other engine damage?

As long as you caught it in time, very little. I have been in a car that was being driven reasonably hard, and a lifter went. It was about 45 minutes before we pulled over and checked. then pulled the push rod out and drove home on 7.

>4. Do you think I have any come back to the supplier?

Possibly, however are these standard lifters, if so he might say you should have asked for the high performance ones.

Just re-read your original post, and seeing as the engine has only done 200 miles, give it a go.

I have an EDA engine in my GD, and as a matter of course, Ken puts good high stres lifters in them.

Andy427
26-08-01, 06:02 PM
Robert

Thanks for the note. I have now idea if the lifters are standard or not but I'll give Brian I call.

Have a good bank holiday.

Andy

Andy427
12-09-01, 05:13 PM
Robert/Graham

Just a quick note to say that I have replaced the faulty rocker and all is well again - just want a few more sunny days to get some miles on the clock. Thanks for the help.

Now that things are settling down, what sort of rpm should be happening at idle when warm. At the moment its about 1100 which sounds a bit fast. If I need to adjust, how do I go about it and are their any books/web articles on the subject?

Cheers

Andy

robert
12-09-01, 05:51 PM
I tick over at aroung 750 to 800rpm, that is where is is nice and lumpy at tickover and sounds lovely through the twin GD pipes, music to my ears!!

Best Regards

Robert
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graham
17-09-01, 09:22 PM
Hi Andy,

I found out one of the problems I had was sticking lifters (they have been standing a while) I replaced these with slightly uprated ones and adjusted the rockers to set preload as per the book. I have roller tip rockers that seem quite good and my next problem is float level adjustment after finding a wrong gasket fitted to primary metering block and main body (it goes on). The idle is set with the idle adjust stop on part of the mechansim I believe, coupled maybe with mixture adjust but get it some where near right then a rolling road adjustment would be absolutely ideal, does anyone recommend anybody??

Graham

Oil under rocker covers is normal I believe. for lubrication of the valve gear.