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andyblackman777

odd knocking on start up

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Hi

I've just replaced my ignition leads ans also fitted a pair of dump valves. Also new sports cats from PNM. Obviously i've had the plenum off. The cars been off the road for about 2 months. When i started it up there was a top end knock, not the sewing machine rattle of loose tappets just a single knock, knock, knock noise.

i decided to leave it running and it finally went away! Sound sweet as a nut now? Obviously i'm slightly concerned, any ideas? i was thinking it might be a hydraulic tappet getting stuck and now freed :P

cheers Andy

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Hi

I've just replaced my ignition leads ans also fitted a pair of dump valves. Also new sports cats from PNM. Obviously i've had the plenum off. The cars been off the road for about 2 months. When i started it up there was a top end knock, not the sewing machine rattle of loose tappets just a single knock, knock, knock noise.

i decided to leave it running and it finally went away! Sound sweet as a nut now? Obviously i'm slightly concerned, any ideas? i was thinking it might be a hydraulic tappet getting stuck and now freed :P

cheers Andy

Yep, hydraulic tappets. Can happen after a few month layup. Probably won't happen again and from what I have read its no reason for any concern, as long as it DOES go away. Mine did the same after a long layup and hasn't done it again after that first warm up.

But it is a big scarey after you have had the plenums off! You start wondering if you have dropped anything down an inlet trumpet and wondering if you should do a quick audit of the smaller items in your socket set....!

I just ran mine at a high tickover for a minute or so 2000 rpm to encourage it to 'pump' back up.. Which I assumed to be the best tactic.

I'd be very interested in a report on your thoughts/impressions on both the dump valves and the sports

cats when you've had a chance to assess them?

Jeff

Edited by jeff_hooper

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Glad you got your car running Andy, Does sound like tappets as Jeff said. Nice to speak to you today, it was a nice chat.

Hope car is fine now!

Dave Walters

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Hi,

test drove the car today its fine no knock on start up this morning so i guess it was a tappet. The exhaust sounds great not to loud and a great sound, Bovs are very subtle not to boy racer so thats good too. I also have no rough idle or missfires on the overrun now so i think the new leads did the trick! :P

The suspension is crap though especially the left rear so i'll have to get some new shocks :P

cheers Andy

ps Dave both those bolts went straight in 5 min job sorry!! :P

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This happened to me last week after a few days non use. Sounded like a single tappet and cleared when warmed up .

So I will look out for a repeat and post if it occurs.

Mike

PS, Mileage is circa 25K +

Edited by MKE40

"Neglect not thy opportunities"

Martock ,Somerset. 1661

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Mike ,

Sounds similar. Out of interest how loud was it ? at 1st mine sounded a bit loud and heavy to be a tappet but it did go and wasn't there the next morning so thats all i can assume it was

thanks Andy

Funnily enough mine did this today, it was 05.30 so the wife was not amused. I've not used it for about 5 weeks and expected it was something like this.

My Evo does it when it's left for a week or two as well, it's the lash adjusters on this car, the oil drains out of them and it sounds like a bag of nails for a minute or two.

Never had it on the Esprit before but was not unduly concerned due to the layoff.

Regards

Fred

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Mike ,

Sounds similar. Out of interest how loud was it ? at 1st mine sounded a bit loud and heavy to be a tappet but it did go and wasn't there the next morning so thats all i can assume it was

thanks Andy

Andy,

Really only a loud tappet sound, I wouldnt call it a knock like a small end or piston slap.

The engine generally is very quiet for its capacity and performance so the small noises stand out.

Mike


"Neglect not thy opportunities"

Martock ,Somerset. 1661

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