Engine characteristic worse after servicing

Engine characteristic worse after servicing

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GO LEO

Original Poster:

108 posts

164 months

Saturday 23rd May 2015
quotequote all
Hi guys,

Just got my Cerb 4.2 back from 12k miles service.
Apparently tappets didnt require adjustment so at the end of the day the car mainly got fluids changed, new filters and new spark plugs. My mechanic also said he slightly adjusted valve timing.

Unfortunately the engine now runs worse at low revs in combination with strong acceleration. There is a stronger hesitation now (also between 2k and 3k revs) than before where this only occurred below 2k revs which I understand is normal for that engine. There is no issue when idling, normal driving, modest acceleration or strong acceleration at revs above 3k, just at strong acceleration from lower revs.

Workshop is about 300 miles away so I am trying to fix the issue without driving all the way back. Mechanic said on the phone that the engine was running fine when he test drove after putting everything back together. He reckoned that one of the spark plug sockets may have disconnected and would have to be put back on but they seem to be all fine (difficult to grab without taking air boxes out).

Before dismantling the whole lot... Any thoughts what the problem could be?

Cheers, Leo

waveydavey1000

148 posts

117 months

Saturday 23rd May 2015
quotequote all
Before driving the 300 mile back to the garage I'd take off the airboxes and check the plug leads are snapped on correctly.
Its a relatively easy job to take off the airboxes, just 5 allen screws on each side plus two hoses on the drivers side and a small pipe on the passenger side.
If you don't fancy doing it yourself, any back street garage would do it in less than an hour.

ukkid35

6,138 posts

172 months

Saturday 23rd May 2015
quotequote all
I am really not trying to be 'clever', I'm just wondering whether it is practical to own one of these cars, anyone one of which will be over ten years old, and many almost twice that age, unless you are willing to pick up a spanner.

The only reason I own a Cerb is because a school friend of mine chose to show off his Cerb one day and I was totally smitten, but I don't think he has ever turned a spanner. His pockets are far deeper than mine and always will be, but as soon as you put your car in someone else's hands you relinquish control, and that I find very scary indeed.

So my question is, can you own a 15 year old supercar without maintaining it yourself?

harry henderson

358 posts

107 months

Saturday 23rd May 2015
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Had mine 4 weeks now, in that time I've had to re fit and repaint the rear lights, replace a fuel hose, replace exhaust hangers, rubbers and clamps and today I replaced a snapped drive shaft. I love it, everything seems pretty simple compared to modern cars. I will be leaving any engine work to the professionals though. However, if I had a few quid I would pay someone else to do it all.

harry henderson

358 posts

107 months

Saturday 23rd May 2015
quotequote all
Had mine 4 weeks now, in that time I've had to re fit and repaint the rear lights, replace a fuel hose, replace exhaust hangers, rubbers and clamps and today I replaced a snapped drive shaft. I love it, everything seems pretty simple compared to modern cars. I will be leaving any engine work to the professionals though. However, if I had a few quid I would pay someone else to do it all.

GO LEO

Original Poster:

108 posts

164 months

Saturday 23rd May 2015
quotequote all
Air boxes wont come off as easily... Seem to be glued on or something. I had already unbolted them before writing this post. I dont want to make things worse without even knowing whether I should try something else first. Hence my question.

Ukkid: I have had this car for 5 years and have survived without being a mechanic and without having deep pockets.
I am just clever enough to ask when I am not sure what to do next. Guess this is what this forum is for...

Leo

Juddder

835 posts

183 months

Saturday 23rd May 2015
quotequote all
GO LEO said:
Air boxes wont come off as easily... Seem to be glued on or something. I had already unbolted them before writing this post. I dont want to make things worse without even knowing whether I should try something else first.
From another Cerbera owner who learned on the job smile

The air boxes were originally sealed on with a product very similar to bathroom sealant (not sure what your engine rebuilt would have used but am assuming similar) so you should be able to unbolt the hex bolts, and then just pull off the air boxes

To replace you can use the same stuff again, or I used draft excluder tape which creates a pretty good seal too, and is much easier to take off next time you need to take them off (*you have to do this to replace the battery on the RHS one so you will be doing this probably a lot in the future!)

There's a few posts from here about replacing the battery on my car so you can probably find some photographs there

HTH

Juddder

Edited by Juddder on Sunday 24th May 00:49

GO LEO

Original Poster:

108 posts

164 months

Sunday 24th May 2015
quotequote all
Thanks Juddder!

ukkid35

6,138 posts

172 months

Sunday 24th May 2015
quotequote all
GO LEO said:
Ukkid: I have had this car for 5 years and have survived without being a mechanic and without having deep pockets.
I am just clever enough to ask when I am not sure what to do next. Guess this is what this forum is for...

Leo
In that case hats off to you. I too find this forum invaluable, I'd be lost without it.

I would have tried to say something useful, but I'm not familiar with the 4.2 airboxes. However the very first thing you said did jump out:

GO LEO said:
Just got my Cerb 4.2 back from 12k miles service.
Apparently tappets didnt require adjustment
I'm happy for others to contradict me, but I would have thought that was very unusual.

GO LEO

Original Poster:

108 posts

164 months

Sunday 24th May 2015
quotequote all
True, and I would be happy to hear more people's thoughs on this. According to my mechanic it is not unusual for AJPs driven on the road (not on the track) and without excessive high revving to not require tappet adjustment. However in the forum I have never heard of someone saying that adjustment wasn't necesary when the car was in for 12k miles service.

leo

TheRainMaker

6,302 posts

241 months

Sunday 24th May 2015
quotequote all
ukkid35 said:
So my question is, can you own a 15 year old supercar without maintaining it yourself?
Yes very easily hehe

All I do is pick up the phone, the car gets picked up from my office or house on a truck and returned serviced and fixed.


jamieduff1981

8,022 posts

139 months

Monday 25th May 2015
quotequote all
GO LEO said:
True, and I would be happy to hear more people's thoughs on this. According to my mechanic it is not unusual for AJPs driven on the road (not on the track) and without excessive high revving to not require tappet adjustment. However in the forum I have never heard of someone saying that adjustment wasn't necesary when the car was in for 12k miles service.

leo
Just an observation, but the number of people who have sufficient experience of AJP8s to make such a statement without merely talking out his backside to try to sound knowledgable (as mechanics are very prone to in general regardless of the car) is tiny.

gruffalo

7,509 posts

225 months

Tuesday 26th May 2015
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I am with Paul.

Very unlikely that after 12k miles the tappets would not need to be adjusted.


fatjon

2,144 posts

212 months

Tuesday 26th May 2015
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Mine was bought at 34k and went to Joolz 3 months ago at 44k for its major service. The valve clearances were spot on.