Oh Dear What Have I Done

[M@tt 77]

i've fitted my new catcam but once i put everything back together i'm getting a stragge cracking noise when i crank it over by hand I'm almost positive the crank hasn't moved 180 but the i guess there is a slight possbility as takign tha cams out was a bit of a ballache so there might be the possibility i did it by accident. however ei dont feel any resistance when cranking it over and the sparkplugs are out.

 

I've taken a vid

 

http://smg.photobucket.com/albums/v230/meb97me/Pug 205 GTI/?action=view&current=MOV00440.flv

 

i would have expected to experience more resistance if the pistons/valaves were hitting each other. i've removed the cams again now and have checked for any broken springs but there weren't any. The hydraulic liftes are all rock hard (not sure if thats good or not)

 

any ideas?

[Dan Ingram 1]

Links not working Matt.

Edited April 6, 2008 by Dan Ingram

[M@tt 77]

http://smg.photobucket.com/albums/v...nt=MOV00440.flv

 

on the vid if you look at cylinder 2nd from left it looks like its opening as the pistons coming up, thats not right is it?

 

i found most of the hydraulic lifters were rock hard so i wonder what with the new cam having greater lift whether the valves were catching ever so slightly on the pistons?

 

i've now taken all the hyraulic lifters out dismantled them all and giving them a good soak in thinners before putting them back in

Edited April 6, 2008 by M@tt

[M_R_205 5 1 Cars]

Some overly lumpy cams require a litle of the head to be machined away,i had this with a PT27 cam, but mine stoped dead, yours may just be scraping?

 

Just a thought...

 

EDIT: piston 2 looks ok to me, the cams pointing towards the cam as the piston is almost at tdc, from my ltd engine knowlage that seems normal...

Edited April 6, 2008 by M_R_205

[boombang 2]

Above could be possible. Every Mi head is slightly different that I've seen - on one particular head a set of catcams caught on the head. Can't remember model number but they were supposed to be direct fit with no modification.

 

Tried them on another spare head and made no contact at all.

 

Variation in the line boring for cams seems to be rather large. IIRC the very early heads I've seen (out of F reg cars) have much neater valve seats and cam bores seem to be lower (i.e. tend to need to mod the head very slightly).

 

Check the side of the heads where the lobes have been touching to see for any scraping marks. The cam shouldn't be damaged at all, but do check and make sure any swarf is cleaned out very well. Don't forget to run the cams in with plenty of lube and 20 mins at 3k revs - defiantely don't let it idle!

[M@tt 77]

cool cheers for the responses i've stripped and cleaned with thinners all the hydraulic buckets just incase any of them were playing up and all feel ok now.

 

http://img.photobucket.com/albums/v230/meb...TI/DSC00441.jpg

 

I'll get it all refitted tomorrow night and check the clearances of the lobes. Problem checking it was i couldn't see what was going on whilst i was rotating it and the missus is worse than useless when asked to help with any car tasks (even getting her to video it was a mission!!) so i couldn't see what was making the noise hopefully it will be somethign nice and simple like it catching.

 

I don't know what year car the engine come out of so fingeres crossed it is one of them early ones

[welshpug 1,657]

now you have the buckets out stick the cam back in and spin it, see if it turns freely.now you have the buckets out stick the cam back in and spin it, see if it turns freely.

[DrSarty 90 1 Cars]

now you have the buckets out stick the cam back in and spin it, see if it turns freely.now you have the buckets out stick the cam back in and spin it, see if it turns freely.

 

Alright Mierion, no need to say it twice....correction, 4 times now!

Edited April 6, 2008 by DrSarty

[Henry Yorke 269 3 Cars]

I have heard the cam catching the top of the rocker cover before. Give Neal at DES a call as he will be able to advise, though Boombang / Boobies worked there for a bit, hence he knows too!

[M@tt 77]

rocker cover wasn't on so it won't be that

[M@tt 77]

sorted it!!

 

can anyone guess whats wrong with this picture

(catcam on the left, old micam on the right)

 

Edited April 7, 2008 by M@tt

[Gibbo GTI 0]

looks like the keyways are the opposite way round lol

[M@tt 77]

aye the bloody catcam had 2 slots for the woodruff key!! I didn't notice this at all when i fitted the key from the old cam. I guess because the cam can be used on the exhaust as well it need 2 settings.

 

well i refitted everyhting and cranked the engine over by hand and luckily no horribe noises just hope the few rotations i did do hasn't caused any damage

[base-1 17]

If you were only cranking it by hand it should be fine. I wonder why they have 2 woodruff key slots, does the cam fit something else aswell with different timing?

[James_m 0]

Let us know your opinions once its up and running M@tt

[M@tt 77]

will do i its all back together now so i can fire her up tonight and 'if' AVO have sent the new suspension bush sleeves through i can refit my rear shockers and take her for a spin

[M@tt 77]

Well tonight with some kindly offered assistance from chris (309pug) i finished putting the last few bits back on the Mi and fitted the new bushes to the rear shockers and fitted them on the car.

 

The engine started up with no trouble and idled fine

 

so then we took her for a drive, i've got to say i could definitely feel the difference. There is definaitely some more low down torque so i'm happy with that. I'm running the number 4 pulley on the catcam inlet which is apparently 108 degrees advance. Spec sheet for the cam states 112 but from reading advice on here it seems some more advance is suitable.

 

However one thing we did notice was that with a sharp blip of the accelerator the engines seems to hesitate ever so slightly. The revs drop but then pick up agin. If you press the pedal normally the revs rise normally, but i'm sure the quick blip shouldn't behave like that.

 

I've attached a few vids

 

 

 

Any suggestions as to a possible cause/remmedy.

 

Tbh it doesn't seem to affect normal driving but i'd like to sort it if possible

 

cheers

[pug_ham 244 3 Cars]

I hope you ran the engine @ 2-2.5k for 20 minutes to bed the new cam in properly.

 

4' less advance could make a difference to how it runs as well imo, might be worthwhile getting a vernier on & setting it correctly.

 

Graham.

[James_m 0]

Might just be the effects of a cam on the standard management? I run a Stage 1 regrind also with a 4 pully and it has a few odd idiosyncrysies.

Dont know if its simular to what your experiencing, but occasionally when the engine is dropping back to idle, the revs go quite low before coming back to a lumpy 1kish

Also get an up/down idle for a bit when cold with rpm actually dropping off if a light throttle is used.

For daily drivers they are best left alone IMO

[Tom Fenton 1,542]

Looks to be rich-bogging to me, look at the black smoke out of the tailpipe when you do it. Most likely a cause of the lumpier cam fooling the AFM I'd say.

[Toddy 7]

Looks to be rich-bogging to me, look at the black smoke out of the tailpipe when you do it. Most likely a cause of the lumpier cam fooling the AFM I'd say.

 

I agree with Tom, maybe worth trying Jamies/Andy's AFM, as yours may need retracking. Can always retard the inlet slightly once you get the shim for your vernier.

[M@tt 77]

took Toddys advice and properly retracked my AFM this evening and its cured it i think!! (runs off to touch something wooden) it was dark when i tested it so couldn't see if its still smoking slightly but the revs certainly don't dip now when you stab the throttle so fingers crossed

 

basically i took the AFM off the car, removed the plastic lid, unscrewed the 4 bolts holding the top part of the case down so that it could be removed and undid the bolt that held the sweeping arm on.(making sure i made a mark of exactly which position it was in before undoing the bolt).

this them left me with this

 

unlike some of the other afm refurbing guides i found that bending the arms of the sweeping contact would not work as the height of the arm on the spindle cannot be changed due to the fact it is screwed down into position. Therefore the solution is to move the circuit board ever so slightly closer to the centre spindle allowing the arm to sweep over a fresh piece of track.

 

So it was a case of undoing the 3 small screws so that the pcb could be removed. I found these screws to be threadlocked in so took quite a bit of careful effort to get them out.

 

it was then a case of elongating the holes slightly so that the pcb could be slid slightly closer to the centre of the afm

 

finally put the arm back on the spindle and check that the arm sweeps across fresh track and once happy tighten the screws back down to hold the pcb in place. Use some threadlock to make sure engine vibration doesn't loosen them and allow the pcb to move.

 

 

tighten the sweeping arm nut back up making sure you screw it down with the 2 markers lining up that you made previoulsy and job done!!

 

i'll have a look tomorrow in the daylight to see whether the puff of black smoke is still there

[KRISKARRERA 2 1 Cars]

That's briliant! Should be stickied! Tis the only proper Mi16 afm retrack explaination I've ever seen, others just refer to the 8v afm.

[KRISKARRERA 2 1 Cars]

.... though none of those screws are coming out on mine - all stuck like fcuking glue! ARGH!

[M@tt 77]

aye the screws on mine were really tough.

 

Make sure you get a properly snug fitting phillips screwdriver so you dont round the heads, it took several attempts at finding a bit that fitted right in properly, but even still one of mine sheared off!

 

you can drill them out if you're careful