2,000 rpm clatter

jeremybarnes · Post by **jeremybarnes** » Tue Jan 19, 2016 6:45 pm

Hello, I recently purchased a 1967 4.2 Series 1 coupe. The car appears to have had a good life, with 80,000 miles on the clock and just a rusty battery tray to show for it. Since purchase, I've drained all the fluids and replaced with fresh, checked brakes, new vac lines for the power brakes, all new hoses under the hood, new fuel lines and rebuilt all three carbs.

I've used "search" to try to find an answer to my question, but to no avail, so I hope someone can help here...

So, my question: upon startup last night, to finalize refilling the cooling system, I noticed a "clattering" noise right at about 2,000 rpm. Below that, nothing, and above that, nothing.

Initially I thought I may have left a tool on top of the engine or the header tank and it was rattling, but nothing. It sounds like the noise is coming from the front of the engine, perhaps towards the top, but it's hard to tell. As I've never driven the car (waiting to put the interior back in that the PO removed), I don't know if it's always made this noise or not.

The engine idles right at 650 rpm perfectly, with no noise, and with 30lb or so of oil pressure. Water temp was about 75 degrees, with the fan holding it there as it idled in the garage.

So, any ideas on my noise? I'm running 20-50 Castrol GTX oil, stock canister oil filter. Should I be worried?

Many thanks, in advance.

Jeremy
Southern California
1E33679

Post by **Heuer** » Tue Jan 19, 2016 7:04 pm

Fan belt idler wheel bearing worn? You can safely remove it completely - it was onlt there to automatically adjust the belt tension for wear. useful in period but now the cars are pampered ..............

cactusman · Post by **cactusman** » Tue Jan 19, 2016 7:14 pm

Idler pulley good suggestion. May also be something as simple at something resonating at a particular engine speed. Get the noise going and just rest a hand or a lump of wood on things like the air cleaner, pipes, header tank etc ...if it vanishes when you touch something bingo. If you think it is within the engine it could be the timing chain. A short length of hose as a stethoscope can assist in narrowing the location of a rattle too.

jeremybarnes · Post by **jeremybarnes** » Tue Jan 19, 2016 11:20 pm

Thanks for the suggestions. That said, and for my information, if it was the idler pulley, wouldn't it make a noise all the time? What would cause it to only happen at a certain RPM?

And if it's the timing chain as cactusman suggests, perhaps you can explain as well why that'd be only happening at 2k rpm? And if it is the timing chain, can that be replaced (or re-tensioned) with the engine in-place (i hope!)?

Thanks again. Will report back what (if anything) I can figure out in the meantime.

Jeremy.

Post by **mgcjag** » Wed Jan 20, 2016 8:56 am

Hi Jeremy.....timing chain can be tensioned with engine in situe....do you have a maintenance manual..if not there is one in the knowledge base section....all adjustment info is in there....noises and rattels can happen at specific revs a friend had a rattling at similar rpm diagnosed as loose cam followers....head is now of being done.....you really need to lift the bonnet an search, or find a local E owner who can help ..all the best steve

Post by **Heuer** » Wed Jan 20, 2016 11:34 am

jeremybarnes wrote:Thanks for the suggestions. That said, and for my information, if it was the idler pulley, wouldn't it make.

Much like an out of balance wheel causes vibration at a certain speed - say 70mph but not lower or higher - the idler can rattle because a combination of factors. It is also the easiest to check, either by tightening the belt or removing it entirely and running the car. As I said, doing so will not cause any harm and it is only 30 minute job to remove or replace.

jeremybarnes · Post by **jeremybarnes** » Wed Jan 20, 2016 7:16 pm

thanks for all the suggestions.

DAVID: I'll pull the belt off tonight and see what happens. If that solves it, I'll make a decision whether to replace the tensioner or just work around it.

I'll report back...

Jeremy.

jeremybarnes · Post by **jeremybarnes** » Mon Jan 25, 2016 6:48 am

Update:

- pulled the belt off completely and ran the engine for a few seconds. Rattle still there. The tensioner pulley spun free, with no vibration or noise, so no apparent issues there

- then i went to tension the upper chain. I dreaded the job terribly, but it turned out to be pretty easy. Using this link, http://www.jcna.com/diy-timing-chain-te ... xk-engines, I built the tool and followed the instructions in the workshop manual to do the work. I have a couple of questions about what I found, and what i did:

1) the book says to push the plunger in and turn the cam anti-clockwise to add tension. I did that, but couldn't get the wheel to turn at all.
2) so i tried to turn the wheel the other way. It probably went 3/4 of a turn. I locked the nut down, bolted everything together again and started the engine. Rattle was exactly the same! Hmmm...
3) i got scared, having turned the wheel all the way clockwise, so I ran it back as far as I could anti-clockwise again, and locked it down. Bolted everything back together again and started the engine. Rattle still there, and still at 2k rpm, but interestingly the rattle was reduced quite a bit.

Sooooo...I guess I just learn to live with the rattle, it seems? It's interesting that it only happens right at an indicated 2,000 rpm, neither above nor below that number, and I mean 100 rpm difference is enough to make it go away. I have about 40 psi of oil pressure at 3k rpm, and the engine idles happily at 650-700rpm. Water temp is solid at 75 degrees while idling stationary in the garage.

Any other ideas, or is it just what it is?

Thanks for listening...

Jeremy.

Post by **mgcjag** » Mon Jan 25, 2016 9:35 am

Hi Jeremy.....did you actually apply some preassure to the chain to see how much play was there......when you push the plunger and try to tighten anticlockwise there will be some resistance .....you do need to turn it with a bit of effort to tighten the chain.....then as per the manual turn the engine a little each way and recheck the chain tension......as i posted above i suspect it could be loose cam followers....a friends made a rattling at similar revs only.....get the rattle going and have a listen on the cam covers with something like a large screwdriver one end touching the cover and the other to your ear....possibly you will hear the noise comming on the exhaust side cam....next step pull the cam covers and check the followers....good luck.. Steve

dal2.0litrefrogeye · Post by **dal2.0litrefrogeye** » Wed Jan 27, 2016 10:23 pm

Hi , have you tried pushing the clutch pedal down , maybe eliminate clutch and or gearbox ?

abowie · Post by **abowie** » Wed Jan 27, 2016 11:27 pm

jeremybarnes wrote:Update: Rattle still there, and still at 2k rpm, but interestingly the rattle was reduced quite a bit.

Jeremy.

Try tightening the chain a bit more. Use something to get a bit of leverage on it. It won't break and you can't really overtighten it without being a gorilla. DON'T DROP THE LOCK NUT.

Other suggestions are maybe the aluminium splash plates under the air filter; these can rattle and vibrate.

Consider adjusting the rear engine stabiliser. Essentially, loosen this off until it is free, then gently tighten the nut down until it is JUST tight.

Finally, spend a good 10 mins or more trying to locate the source of the rattle. I like to use a really big screwdriver like a stethoscope. Just mover over the whole engine surface and see if you can localise it. Be careful near the alternator belt :-)

jeremybarnes · Post by **jeremybarnes** » Mon Feb 22, 2016 6:28 am

So, next update...

Borrowed the proper tensioning tool and tried the project again. I absolutely cranked down on the tensioner, but it didn't budge even a tooth on the plunger, so I can only assume it's as tight as it'll go. Should I go the other way on the tensioner (clockwise), and see what happens? Seems like a bad plan, somehow...

I did the long-screwdriver-to-the-ear trick, and i honestly can only hear a bunch of whirring and whooshing from inside the engine, no localized knocking. The noise is still coming from the front of the engine, i'm 99.9% sure of it, though.

Any other ideas? Any chance the chain has stretched sufficiently (at 80k miles) that it needs to be changed, as there's no tensioning left in it?

Thanks,

Jeremy.

Post by **mgcjag** » Mon Feb 22, 2016 9:30 am

Hi Jeremy...is there slack in the chain....have you tried moving it on either side to check the tension.. is it tight one side and loose the other...if you cant actually tighten using the tool then try loosening it then checking the tension is loose then tightening......you say you are using the correct tool...it is pushing in the release pin to disengage it.......

Tony · Post by **Tony** » Mon Feb 22, 2016 10:18 am

I presume you have set the engine to 2000 Revs so the rattle is continuous and then gone looking for the noise. if you took off the fan belt and ran the engine for a short while it would elimate the water pump and alternator.
The odds are you have already tried this but you never know.

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

The 'E' Type Forum

2,000 rpm clatter

#1 2,000 rpm clatter

#2

#3 Rattles

#4

#5

#6

#7

#8

#9

#10

#11

#12

#13

#14