Vn V6 Engine Top-end Rebuild

[jules]

a while ago i described how my VN is really rough on idle - it lurches forwards, as if something is getting caught and stalling the engine or transmission momentarily.

it might have been Garth who suggested the torque converter.

i'm now thinking it could be the engine mechanicals, as also:
-sometimes when cranking, it just stops, as if it's at the top of the compression stroke and the starter motor can't turn it, then it gets free and fires straight away.
-the idle is smooth, but 'snags' every few seconds, dramatically dropping revs before recovering. occasionally stalls but not often.
-smoke on startup, indicating worn valve guides (or seals?)

so i wonder if it's a sticking valve? anyway since the timing chain i believe has never been changed (170k on the clock) i've decided to overhaul the top end.

anyone done this before on a VN V6? i plan on taking a few days leave and doing it, but the hard part is ordering parts. anyone know what i'll likely need to replace in advance?

 

[grover]

are you doing the heads yourself or sending them to someone else?you will obviously need a valve regrind gasket kit{head gaskets rocker covers etc.if you are doing the heads it may pay to rip your cam out if changing timing chainetc and renew cam if needed and lifters if you change cam.

 

[jules]

i'm not really sure yet. i've never done this before so it will be a learning experience. i'm competent enough to pull it all apart and with a bit of luck put it all together again, but i don't know all the tricks about what to look for, what to replace, etc.

i'm not building a 10 sec tyre shredder i just want it to run good and be reliable.

i will need to educate myself on this but i thought you could grind valves/seats manually with paste and turning them by hand in the seat?

i'll probably buy a dial gauge and measure cam lift and stuff, if it needs replacing i'll bite the bullet but i'm trying not to spend too much.

 

[grover]

you can do the valves yourself but if you are blowing smoke at startup and your seals arent the problem it would probably pay to get new valve guides fitted.the easiest way to check your cam for wear is by inspecting the lobes,if they are pitted,throw it away.doing it yorself is the best way to learn,but these little excursions can be expensive.dont you just love spending money on cars!!!!

 

[Garth]

first thing first, take pictures of everthing sport, make sure you number everycable in the engine bay, and take extra care when handling sensors.


tools needed

gasket scraper, (and no, a knife wont do, it will scratch surfaces)
ridge reamer (for making edges smooth and taking of any burs)
engine balancer puller (big socket and lot's of muscle will get it off)
micrometers
telescoping guages
cylinder surface hone
tap and die set
oil gallery brushes
cleaning solvent
dail indicator set (to check travel and runout)
valve spring compressor's (kinda obvouse)
that should be it tool wise

things to replace

head gasket's
new thermistate, (a new engine will run hotter then a old one) entire valve train assembly's




there is heaps of stuff to replace, give me a day or 2, ill make up a list and send it to ya, email [email protected] so i can forward them on to ya

cheers
garth

 

[jules]

ok thanks guys. yes i love spending on my car.. NOT! i love working on it, but it's not a street machine my aim is minimum $$$.

garth i'll send an e-mail, thanks for your help. that list is already scary. ive got some of that stuff, i replaced the balancer once already and that was a bijzatch of a job, hopefully easier this time.

 

[Locksmiff]

Depnding on how much you don't want pay Jules. I know you want to do it yourself and I too was going to my own heads, assembly that is. I got a place near me called PAVTEK to all my machine work on my old motor (sold it the other week). I was going to assmeble the heads myself, the guys said, your only gonna save $30-60 in labour, so I said, bugger it, for that little in labour, you might as well do it. I spent $1000 on mine, so the heads wern't just a reco, but porting etc as well.

I think most head reco's are around 200-300 ish.