Engine noise after mods

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Jun 5, 2002 | 01:27 PM

Gareth

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Joined: Aug 2001

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From: Brackley Northamptonshire

Engine noise after mods

I have just finished installing CompCams 1.6 steel roller rockers, a Comp Cams 0.049" lift cam and updated my springs to suit. Everything is now back together but the engine is a bit 'clattery'. i have taken the rocker covers off but this only improves things slightly. I have run the engine on idle for about 20 - 25 minutes to fill the lifters what next? I have also noticed a small amount of wear on one of the roller tips, despite lubing them up - should this point me in any direction?

I'm deparate to take it for its maiden voyage but obviously don't wanna do some damage.

Oh and one final real dumb question - how do i post pics? It looks really easy but all I get in the dialogue box is [img] type stuff.

Jun 5, 2002 | 01:56 PM

grumpyvette

Pro

Joined: Oct 2001

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From: loxahatchee fla

Re: Engine noise after mods (Gareth)

first thing is you are NEVER supposed to break-in a new cam and lifters at IDLE, thats an excelent way to loose a cam lobe due to not enough oil being thrown from the rods to keep the cam oiled, the first 30 minutes of running time should ALL be in the 2000rpm-3000rpm zone.
next did you also check your piston to valve,retainer to valve guide,retainer to rocker arm,rocker arm too rocker stud, and push rod to cylinder head, clearances? if you have clicking something someware is hitting something or your valves are not properly adjusted, stop and find out WHAT is causeing the noise before going any further!, BTW comp cams cams use very fast return ramps unlike CRANE,CROWEr,ERSON,ETC. so that may be what your hearing (the lifters clicking as they return to the cam lobe base circle but thats not likely as thats normally barely audible if the valves are correctly adjusted

Jun 5, 2002 | 02:09 PM

Zix

Le Mans Master

Joined: Jul 1999

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From: Phoenix AZ

Re: Engine noise after mods (grumpyvette)

I agree...first thing I would do is check your valve adjustment and make sure everything is good. When you are adjusting the valves take the rocker off and make sure the stud is tight. Also look at the rocker where the pushrod sits and make sure there are no abnormal wear marks, there should only be a nice circle-mark in the center. Are you using guideplates? If so, make sure the pushrods are not contacting any of the guideplates as well. Take a look at the underside of your valve cover and see if there are any wear marks from the rockers contacting the cover. When you tighten down the rocker make sure the lifter is tight...you may have a spongy lifter in there as well.

Jun 5, 2002 | 02:37 PM

BLUE ONE

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Joined: Apr 2002

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From: loughborough Leics ENGLAND

Re: Engine noise after mods (Gareth)

Gareth, did you check retainer to guide clearence ? If you used your std retainers i think this could be your problem. I could not get more than about .500" lift without hitting the guides. If it is a .490" lift cam + 1.6 rockers you are definately into metal to metal contact !!:eek: :eek:
The differernce is being absorbed in the roller lifter and valve train which could explain the wear or damage on your rocker arms.:crazy:
I would check things through and put your 1.5 std rockers on as a starting point.
Did you remove all of the tabs on your rocker covers ?

You are not that far away from me and if you need any further advice don't hesitate to contact me.

Mark :D

Jun 5, 2002 | 03:38 PM

Gareth

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From: Brackley Northamptonshire

Re: Engine noise after mods (grumpyvette)

Eeek! I'm surprised this is not mentions in the installation instructions. I was worried about clearance issues, but the only ones I came across (I may have to look harder) were the spring bases were too small for the new springs so I had to enlarge the base. The other thing I was watching for was the push rods on the guides and the push rods against the cylinder head. As for the rest I had an 'expert' looking over my shoulder - but I'm not to sure of his experience with this sort of set up. I suppose my big problem is that this is my first rebuild and I don't really know what stuff should sound like!

Jun 5, 2002 | 03:52 PM

Gareth

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From: Brackley Northamptonshire

Re: Engine noise after mods (BLUE ONE)

Great to hear from a 'local boy' and so close.

I bought all my mod stuff through JEGS, there help desk were excellant so I made sure that every thing went together and I got all new retainers too. My heads have been ported and I have new guides - may I'll check these out 'cos they are not standard.

I have not removed the drip tabs from the covers, and I was hoping that removing the covers would would quieten things down, may be it has a bit. I could not see any evidence of wear on the tabs - this maybe because the steel rockers are quite small.

I you get a chance have a look at our 'Clubs' site http://www.americanv8.co.uk my black '88 is in the projects page. We'll have to meet up some time!

Jun 5, 2002 | 03:59 PM

BLUE ONE

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From: loughborough Leics ENGLAND

Re: Engine noise after mods (Gareth)

Yes i will have to come over some time and meet. My vette is in bits but should be up soon !! I know most of it inside out so let me know how you are doing. E mail me if you need more advice, i am busy tonight but i think we can work your problems out.

Mark

Jun 5, 2002 | 06:33 PM

Gareth

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From: Brackley Northamptonshire

Re: Engine noise after mods (BLUE ONE)

Great, E-mail the club website with your contact details (if thats ok) then I'll be in touch, hopefully with how wonderful all my mods are! I'm supposed to be in the Coventry One Classic Car rally this Sunday and there's still so much to do!