Rattle on cold start up?

4.2 tr7 · Post by **4.2 tr7** » Wed Oct 03, 2007 11:34 am

Hello hope someone out there can help. I got rid of my TR7 this year and bought myself a Griffith 4.3 big valve (pics to follow) still miss my 7 though, anyhoo problem is I've been enjoying the griff through the summer and had no problems, its got 43k with a fsh however since the weather has changed I've noticed the engine has a rattle on cold startup similar to that of a rattly mk3 escort but not as loud and it stops after a few seconds, is this normal or is there some nasty bills coming my way?

CastleMGBV8 · Post by **CastleMGBV8** » Wed Oct 03, 2007 2:02 pm

Anon,

Sounds like the hydraulic lifters are draining down, not unusual and as long as the rattle dissappears after a few seconds nothing much to worry about.

It can also be caused by a filter with a defective non drain back valve and it might be a good idea to try fitting a good quality new filter.

Kevin.

Lewis · Post by **Lewis** » Wed Oct 03, 2007 2:02 pm

Probably just a lazy tappet taking some time to pump up - sort of a "taptaptap..tap...tap..........." then fades away? If so, probably that.

I wouldn't worry about it too often - the oilways in the tappets tend to clog up a little, so when it's thick (cold) it doesn't pump them up until it's run for a few seconds.

Changing the oil may alleviate the problem

Dammit, dual post, what he said ^^

ppyvabw · Post by **ppyvabw** » Wed Oct 03, 2007 2:06 pm

Is it a tapping or a heavy knocking. I have a heavy knocking when I start up. Sounds like the mains or big ends, but after 25000 miles it seems to have done no damage.

Otherwise I conquer, it's probably just a tappet and not worth worrying about

4.2 tr7 · Post by **4.2 tr7** » Wed Oct 03, 2007 2:17 pm

Hello the oil was changed recently and is still golden, it's definately not a clunking noise more of a tap a tap tap and only lasts for a couple of secs then everything is as it should be. If it is'nt anything to worry about I'll go back to enjoying it somemore thanks for your advice

kiwicar · Post by **kiwicar** » Wed Oct 03, 2007 2:25 pm

"changed the oil recently", by any chance used somthing other than 20/50?
Mike

4.2 tr7 · Post by **4.2 tr7** » Wed Oct 03, 2007 3:02 pm

Hello the garage changed the oil/filter last month when it went back for an oil leak, not sure what grade they used but presume it was MOBILE 1 0W40, I've read in Steve Heath's "bible" that there's some argument on oil choice I'm no expert on anything engine related so tend to follow what the manufacturer recomends maybe I'm just a little paranoid about the car as the warranty has ran out, cheers

Phil.

ChrisJC · Post by **ChrisJC** » Thu Oct 04, 2007 7:24 am

I would say that 0W/40 is way too thin for that engine......

I run 20W/50 in both my V8's. But I'm not sure of your engine spec.

Chris.

kiwicar · Post by **kiwicar** » Thu Oct 04, 2007 1:34 pm

this is one of the most common rover threads on here, someone changes the oil to somthing other than 20/50 and posts on here that they have a "top end rattle" the hydraulic lifters on anything but the late 4.0 and 4.6 engines rattle on anything but 20/50. The rest of the enging needs 20/50 aswell as the oil pump was designed to use it and tends to drain back if wou use thin stuff.
Mike

4.2 tr7 · Post by **4.2 tr7** » Thu Oct 04, 2007 4:09 pm

It was a TVR garage that changed the oil I'll give them a call to find out for sure but it was'nt rattling straight after it went there only when it's cold outside, I used the car when I was working nights and I finnish at 5am friday morning and it was then I first noticed it. I just presumed they had used 0W40 again reading to many books but if they did I'll change the oil to 20/50 when I take it off the road for the winter and see if that works, cheers

Phil.

p.s been in my books again spec as follows:

bore: 94mm
stroke: 77mm
compression ratio: 10:1
cylinder head: ported balanced and polished
valves: 42.8mm inlet, 36.8mm outlet
power: 300approx blackpool donkies & 320+lb/ft

Quoted in Steve Heath's book

TVRTASMIN · Post by **TVRTASMIN** » Thu Oct 04, 2007 4:19 pm

You have probably got 0W/40 in it or something near which is no good.
Better to use Mobil's Motorsport 15W/50 if you want a full synth, otherwise a good quality 20W/50 changed regularly.
The serpentine engine will just about tolerate thin oil but not your pre serp.

Did you get it from Tony at HHC?

4.2 tr7 · Post by **4.2 tr7** » Thu Oct 04, 2007 5:14 pm

yeah I bought it from Tony, well his son Richard really, nice people to deal with I love the griff but miss the stealth and amusement of my old TR7