Heads Off - Some Advice Needed

[kilauea 7]

After a lot of huffing and puffing today I finally got my head off. I've decided to just give it an engineering place to have it checked over and reconditioned. But in the meantime if anyone can offer any advice on these I'd really appreciate it....

 

I notice a fair bit of carbon built up on the pistons. I just wonder what the scope if for cleaning it off without disturbing the piston liners? Didn't want to rub them too hard in case they moved.

 

Quite a few cables off the loom have shielding that is cracked and missing. I thought about patching them up, but do I need to use something "heat proof"?

 

Cheers,

Gaz

[matty_gti 20]

I'd just give them a wipe with a rag and some fuel, gets rid of the carbon. With the wiring I'd deffinatly replace the bits that are next to somthing hot.

[CosKev 16]

I would leave the carbon on pistons and top of liners alone.

 

Made the mistake of cleaning the tops of my pistons and bores when I had a mini many years ago and it burnt oil afterwards

[kilauea 7]

Hmmmm, conflicting opinions. There is quite a bit of carbon on them as its been running rich (plugs were v. black and sooty after only a few hundred miles). I suppose the question is what benefit will clean pistons give me?

[EdCherry 34 1 Cars]

Nout at the minute it isnt running! LOL

 

Id just leave them mate, get the fueling and ignition right when its back together and they should clean themselves up a bit although they will always have slight carbon deposites.

[kilauea 7]

Fair do's. I'll leave them be and try and burn them off with my right foot when its back together

it does make me wonder if any of that cleaning s*it in optimax et al actually does anything.

[EdCherry 34 1 Cars]

Personally I believe it does work, from my experience with BP Ultimate 102 (Far and few between stations that sell it) it has a vast significance in appearance, and smell (get high off it just fueling the car!) and it does affect performance in my eyes. Now wether it really affects how clean the engine is im not sure internal wise as I havnt taken it apart yet.

[kilauea 7]

Oh yeah, totally agree it affects the performance. When I have been caught out and had to put 95ron in it runs like a dog in comparison. Even in my last car which would adjust for the fuel it felt markedly different.

 

I just question the cleaning effect really. But now I'm a dab hand at stripping engines I'll be giving it a clean every 10k

[Masekwm 2]

As said leave it otherwise it'll smoke afterwards (as I was told by a RR mechanic)

[DamirGTI 342]

If the carbon deposits are thick , if theres big amount of deposits (especially burnt oil deposits if the engine consumes oil) on the piston crows they might provoke pre ignition/detonation (kinda like overheating spark plug tip because of the wrong heat range ..) in this case id remove just the big flaky bits off from the crowns with an soft scrapper , however you must seal the gap in between the piston and cylinder wall first , seal all around with grease as the specks of carbon will travel down in between the piston rings and will choke the ring groves so keep an eye on this and throughly seal the gaps first if you decide to clean the crowns ..

 

Also , under no circumstances - do not use sanding paper ! neither for block/liner cleaning nor the piston/piston crown cleaning as the abrasive/metal particles from the sanding paper usually ends up (again) in-between the cylinder walls and piston (piston rings) and this abrasive particles will accelerate piston ring/cylinder wall wear ! .. this is particularly important during the engine rebuilding with new parts .. use plenty of WD fluid and scotchbrite pads for cleaning and soft scrapper for removing thicker layers of deposits or remains of old gasket on the mating surfaces , when done wash off surfaces with brake cleaner ..

 

Theres a few spec. products on the market for use on car/marine engines called something like "de- choke" , now i didn't try this stuff myself but they claim that this product removes majority of carbon deposits from the engine internal parts (i'm just unsure weather this product melts carbon deposits of break them loose in bigger particles ?!..) so you might try with that

 

Afterwards take the car to the RR for fuel mixture and ignition timing adjustment , as the black sooty deposits on the spark plugs indicates rich fuel mixture and that's not good for engine as well as lean mixture ...

 

Damir

[kilauea 7]

Thanks for the tips Damir!

 

I decided to give it a bit of a go, as it was pretty caked and had some corrosion on two of the liners, presumably from when the gasket failed.

 

 

 

I put some grease round the edges and popped a vacuum cleaner in there sucking away as I rubbed it off. I used some wd40 and brake cleaner to finish and then gave the pistons a good vacuuming to get any dust and carbon out. I didn't try and remove every last bit but it looks much better now.

 

fingers crossed it doesn't smoke!!

Edited June 8, 2009 by kilauea

[wracing 19]

just think a few thou of carbon increased compression = increased performance. as said remove any flaky bits. no point been to clean!

 

 

james