Valve, Head Cleanup

[Twinky]

Hey guys,

 

Finally got the rolla running again after finding out the points were fried but she still wasn't running right.

Every time I'd quickly pull the throttle the exhaust would throw out a cloud of smoke, also a loud crack would emminate from the exhaust.

Apart from that the idle and exhaust note was just not right. I checked and recheked the idle vaccume, play with the dizzy timing and nothing seemed to make it better.

 

 

 

As this beast is going to be the daily I decided that I should give it a good cleanup and get it running right.

Soo I started pulling it apart..... I made sure that I took photos all the way so that i could identify what hose went where etc etc.

 

 

The very first thing I noticed was that the exhaust was only being held on by one bolt...... All the other bolts were only finger tight if even that, so that explained the bad exhaust note/cracking pop on what.

After a painstakingly long period of time I finally managed to get the intake/exhaust off I'd seen another possible symptom of bad performance. Just pure plain bad gasket placement and bad use of gasket goop.

It was everywhere.... Also it seemed that a slight oil leak (over a very long period of time) had made it's way into the inlet and exhaust on the head because of the poor gasket seal. So i then decided it's time to rip off the head.

Now this is the very first time that I have even thought of doing something like this. I've swapped a motor and changed a clutch before but nothing like this, so if I'm doing anything wrong don't hesitate and point it out.

So after following the trusty toyota k series engine manual I unscrewed the head bolts in the correct order and correct incriments. I then took out the pushrods and bagged them in order, numbering each one.

 

 

And hey presto there is the head!

 

And another dodgey thing I found...... Wtf was ment to be bolted on here????? (on the firewall side of the head)

 

Instantly i saw carbon/sludge buildup, yuck! The top of the pistons, valves and yes even the valve seats had this shit on them! No wonder this thing was running like crap!

No kidding there is like 1 - 1.5mm of crap on them!!!!!

 

So I bought a valve spring compressor from supershit auto for $50 and away i went cleaning and sanding and polishing.

After taking the first spring off and gently seducing the collets to come off the stem I found that the stem seals were almost non existant, except for the remmenants left by an obliterated one. I looked into my gasket set and found some shiny new ones! hoora!

I used some degreaser first up to get rid of the loose/oily buildup and then attaked the gunk with a fine chisel, carefuly scraping away the buildup. I then sanded it off with 200 gritt sand paper (wet & dry), soaking the sandpaper in degreaser so that it was not too harsh on the metal. After cleaning the gunk off with the 200 I buffed it out with 1200 gritt. Unfortunately there is some very extremely shallow pitting on the valves, combustion chamber but luckily not the valve seats. This ment I didn't get a mirror finish poilish with the 1200 gritt but meh..... It is a shiteload cleaner.

 

Exhaust ports slightly cleaned up (yet to attack it with some sand paper)

 

A picture of a very dirty, dirty valve!

 

A shiny squeaky clean valve!

 

A shiny squeaky clean valve next to the dirty intake valve

 

Clean valve next to a dirty intake valve(slightly cleaned face)

 

To hold the valve in something suitable( I didnt want to clamp the valve so I didnt damage it) I used a socket and placed it into the exhaust port, held firm enough for me to clean it up.

 

After a few solid hours I finally finished one cylinder and called it a night, and yes I did coat everything in engine oil as I put it back together. By the way all of the cylinders looked like cylinder No.3 I had just slightly attacked the others to see how bad they were.

 

I don't think there is a better way to understand engines than pulling them apart and squishing them back together!

In a few days time I will finish the cleanup and reseal the engine, fingers crossed.

 

Any hints or tips would be mutch appreciated!

 

Will keep you updated!

 

Cheers!

Edited April 27, 2010 by Twinky

[Tally]

Mate looks like your doing an excellent job mate.

 

I'm sure some guys could give you a few pointers.

 

good on ya for giving it a go

[Twinky]

Oh and a quick question, those blocked off water holes (witch are brown sludge in the last photo on the bottom half of the head) are they ment to be blocked by the head gasket??? I am unsure as to why they are there but are blocked off by the gasket.

[Trev]

All I can say is I hope you lap the valves in, Other then that good job and It is good to see a member pick up a manual and get in to do something like this :)

 

BTW, Did you degrease the engine before taking the head off cause it is mightly clean.

[Twinky]

I took the head off and then degreased it. The rest of the engine is reletavely clean. No I haven't laped the valves as i don't have the proper tools. In saying that the valves sit in very nicely so I hope they are fine.

I'm sure that if the engine was running with all that crap on the seats then it should run fine now.

[Trev]

I took the head off and then degreased it. The rest of the engine is reletavely clean. No I haven't laped the valves as i don't have the proper tools. In saying that the valves sit in very nicely so I hope they are fine.

I'm sure that if the engine was running with all that crap on the seats then it should run fine now.

 

You can't actually see seat clearance via eye, It is found via vacuum down, Carbon can actually seal up gaps and ou have removed the valves so it would be best to lap them., It costs approx 20 bucks for the lap stick and paste.

[RedKE30]

A valve lapping tool should only set you back ~$20. Then all you need is the cutting cream, not sure what that's worth though. Valve lapping is fairly easy, I learnt by picking up the tool and trying it myself.

 

Looks like you're doing a great job though. Love your cleaning.

[Twinky]

Cool I thought it was going to be a bit more expensive than that. I'll check out the auto stores 2morrow.

[philbey]

Yeh lapping is straightforward, a lapping tool is a wooden stick with a suction cup, just squish it onto your valve with a bit of paste on the seats and spin it back and forth. As mentioned it's about 20 bucks worth.

 

The shit in your cylinders is all the oil your buring coming in via your valve stems.

 

It would be wise to get the head faced seeing as you've gone to all this trouble; it shouldn't cost much more than about 50-60 bucks. Aluminium heads tend to get out of shape when you unbolt them.

[Twinky]

Yeah at first I thought lapping was like doing a regrind but that sounds quite simple.

Somehow I think the previous owner never looked after this motor. I thought I was a dodgey backyard mechanic......

 

Cheers guys!

[Felix]

I just wire brush valves to clean them up. Put a wire brush in a drill, clamp drill to edge of bench, brush valves.

 

That head has had the welsch plug at the back of it welded up. Good thing, as they can pop out and quickly cost you a motor.

 

Take just the bare head and valves to a machine shop, get them to skim the head and also do a 3 angle job on the valves. Should only cost $100-150.

 

You could look into some umbrella type valve stem seals (escort 1600 maybe). The overhead oring type on those early 3k heads suck, and would be a major contributor to all that oil buildup in the combustion chambers.

[snot35]

Nice work!

 

What sort of head is that out of curiosity? They're decent sized ports but it's got the weird old valve sealing arrangement.

[Felix]

It is a 3k bigport.

[Taz_Rx]

Yeah was just about to say its a 3kbp. Ports (obviously) give it away but the other indicators are also the welsh plug and valve stem seals Felix mentioned.

In terms of the VSS, you can get yourself some second hand or (preferable) new 4k style stem and fit them into the 3kbp head. Then you can use the much better design 4k type seals.

 

Did you snap any bolts when taking out the 3x "hot-box" bolts were the inlet and ex manifolds bolt together?

If you did I suggest trying to find some extractors for when you re-assemble.

[Twinky]

I didn't know it was a 3kbp..... I have the new VSS to put in from the 4k vrs kit. All the bolts are still intact thankfully .

Could someone post a pic of a normal 4k combustion chamber? I had no idea it's a 3kbp. kewl......