Head surface prep?

[RunninWild]

Getting ready to throw my aaz head on my 1.6 block in the next week or 2. I've had this head for the past 10 months or so sitting in bubble wrap. I'm not sure what's happened to it but the mating surface isn't perfect. It has a few small scratches in it. Running my finger I can't feel any imperfections but there is one spot I can feel if I drag my nail over it. It's below  the valves and the water passage in this pic.

Anyone think I'll have any problems with it? Should I use some kind of gasket sealer? Would the 1.6 gasket be a better idea over the 1.9 gasket? I'm assuming wet sanding the bigger scratches would do more harm then good?

[libbydiesel]

If there are any raised edges where metal has been displaced and now is poking out above the rest of the sealing surface, you could knock it down *very carefully* with a flat file, taking great care not to scratch below the sealing surface. 

I would recommend using a very light coating of hylomar spray on both sides of the head gasket, on the block, and on the head mating surface.

Don't set the head down on a hard surface with the valve poking out like that.  Those 7mm valves like to bend if you look at them sideways.  I would also be really careful to have the pistons *not* at TDC (roll them down to mid cyl) when you are installing the head if the cam is bolted down like that. 

[RunninWild]

Thanks Libby. It's not really raised up its just rough enough it slightly catches my nail if I run it by. I've read the metal gaskets like a perfectly flat surface which is why I bothered posting. I'm sure hylomar would help seal any of the imperfections. Nothing extreme enough to warrant the use of a file, at the most a light wet sanding but like I said I figure that would do more harm then good.

Any idea what 3 studs would be used for on the head? It came with a little baggie with 3 studs maybe 2 inches long and about 3/4" of spacers in the middle of the studs. I originally figured they were for the the valve cover but after taking a closer look the threads don't fit perfect and I have a feeling theyd be way too tall. Plus Google images looks like the valve cover uses bolts? The studs have the same thread pattern as the coolant inlet/outlet flange mounts...

[libbydiesel]

That sure sounds like the valve cover studs.  You'd have to post a pic for a better guess.

[RunninWild]

Yeah they are the valve cover studs. Its weird I cant thread them in by hand though...

[RunninWild]

Should I be able to tell the head gasket size from the tab of gasket sticking out the side of the head? Of do I need to pull the head to find out. I cleaned all the gunk off the tab but it doesn't look like there are any holes, notches or divits or anything to signify the gasket size. I have 2 old gaskets in my parts pile that have the notches on that tab. Any suggestions on how I can figure this out without physically measuring the protrusion?



Also curious if anyone has any suggestions on where I should start with pump timing on my frankenengine with aaz Giles pump and 1.6td injectors? The few posts I've been able to find on the topic seem to be all around 1.0?

[libbydiesel]

If it doesn't have notches on it, there's no telling.  Even if it did have notches, I'd measure the piston protrusion just to be sure.  It doesn't take more than a set of feeler gauges and a straightedge.  If you want to avoid down time, you could order all three sizes and return the one you don't use.  Make sure the piston tops are completely clean for measuring.  The normal carbon buildup can make the measure go from a 1 to a 3. 

[RunninWild]

Looks like I'm going to have to do it the proper way and just measure it. I ordered the timing tools kit from prothe,  any idea if the dial indicator would be compatible with a magnetic base mount or is there something special about the timing dial indicator?

I'm more then likely going to be finding tdc by the position of the cam lobes then marking then marking the block and crank sprocket. The engine is installed on a Suzuki transmission with no view plug to locate it on the flywheel. Because I'll be playing with the crank measuring protrusion if for some reason my markings disappear tdc should be pretty easy to find with the dial indicator as well eh? I just want to be sure it's timed properly as I'll be messing with the physical and pump timing and would prefer to not run into any issues.

Would you recommend doing anything to my Giles pump prior to install? I bought it second hand and I'm unsure when it was last used. I've had it stored indoors and have never seen it run. Would filling it with seafoam or something similar for a few days be a good idea to ensure its not gummed up?

[RunninWild]

Is a plug tap alright to use to clean the head bolt threads? I can't really justify the $80 arp wants for a chaser and cant find affordable chasers anywhere else.

[libbydiesel]

Are you talking about the threads in the block?  I have a couple head bolts that I cut channels in with a dremel cutoff wheel.  They work fine for chasing the threads. 

[air-cooled or diesel]

i personally never have used a head gasket sealant, none of your scratches seem out of the ordinary, the one by the rear of the water jacket seems big, but i dont think its a problem. i dont think you want to sand it, the machined surface is made to mate with the head gasket, the block side too. ive never had a problem not using a hylomar spray. not to say its better to perhaps cut off a few head bolts so you can guide the head down, after spraying, and installing, otherwise head and gasket, i find i have to line it all back up, takes two people to get the head on,  you have the exhaust studs? i put them in with red loctite, the timing tensioner takes a stud, and for the side water flange you need a special bolt+stud coming out of bolt(6mm). maybe the other water flange you can use bolts or studs, i think i find bolts work better.

Looks like I'm going to have to do it the proper way and just measure it. I ordered the timing tools kit from prothe,

so you have a good giles pump and got junk, dump prothe timing tools&dial, send them back!!at once,,you want good timing tools for good parts and a good job, i have blue point tools, and a good dial, and metric dial will do(if it measures to 0.01mm,+/-0.002mm), you now need a german injector pump timing hole dial holder, adaptor, screws in(metric).

[RunninWild]

I'm more then likely going to be using head studs so psitioning the gasket won't be difficult. As for the water outlet studs I'm going to try and reuse the one's from my old head before I try and track down some new ones.  I honestly forgot about those studs but have ordered new hardware for everything else.

I bought prothe timing tools because I cant justify sending over $100 on tools I'm only going to use once or twice. To be honest I've bought a few things from him in the past and never had bad experiences. That being said I'm careful what I do get from him but I've never read about people having had problems with his timing tools.

Seeing as my new head is going to be on the line I may as well add a new timing belt/tensioner. This project just keeps getting more and more costly...

Would a 5" cutoff wheel cut an ideal size channel in the threads? I don't have a dremel. I've found plug taps for $12 if you think it Would be sufficient assuming I'm super careful not to damage the threads?

[libbydiesel]

Looks like I'm going to have to do it the proper way and just measure it. I ordered the timing tools kit from prothe,  any idea if the dial indicator would be compatible with a magnetic base mount or is there something special about the timing dial indicator?

A friend of mine gave me his Prothe timing dial indicator and adapter when he sold his IDI.  The back of it is just flat with no accommodation to mount it to a typical dial indicator base.  The Prothe set seems fine to me.  The knee-jerk reaction that everything from Prothe is junk is not really justified.  A lot of it is, but some is not.  It gives an accurate reading and the adapter is actually a simple and well made tool.  I have another version that I got a decade earlier also and that adapter is actually a lot worse.  I don't tend to use either set as I typically use my pulse adapter. 

I'm more then likely going to be finding tdc by the position of the cam lobes then marking then marking the block and crank sprocket. The engine is installed on a Suzuki transmission with no view plug to locate it on the flywheel. Because I'll be playing with the crank measuring protrusion if for some reason my markings disappear tdc should be pretty easy to find with the dial indicator as well eh? I just want to be sure it's timed properly as I'll be messing with the physical and pump timing and would prefer to not run into any issues.

TDC cannot be found with the cam without knowing first that the cam is perfectly in time.  How can you be sure?  I would wait until you have the head off to find TDC for #1.  You can use a dial indicator.  Take note of the highest reading and roll the engine exactly to that point. 

Would you recommend doing anything to my Giles pump prior to install? I bought it second hand and I'm unsure when it was last used. I've had it stored indoors and have never seen it run. Would filling it with seafoam or something similar for a few days be a good idea to ensure its not gummed up?

Getting the vane pump wet with something like that may help if the pump has sat long enough to dry inside.

I would definitely *not* use red loctite on exhaust studs.  That's a really bad idea and completely unnecessary.  If you ever need to replace a stud in the future (not uncommon) the red locktite will make it a right PITA.  If someone else is replacing a stud and they do not know about the locktite, they will likely snap off the stud or mess up the threads in the head.

Prior to using hylomar I had a couple head gaskets weep slightly at the oil channel to the head (between #3 and #4) after 20,000 miles or so.  I've seen that issue very frequently on older engines.  Some will also weep at the oil return holes.  Since using hylomar I have not seen that issue.  The $20 can is enough for 3 head gaskets.

5" cutoff wheel would work fine to make the channels in the bolts.  Plug tap would work ok although I would prefer using the bolt method as it is unlikely to remove any metal material and weaken the threads. 

[Toby]

A better answer than a thread chaser is the proper 12mm tap. It is about $8. Beware: spark plug taps are NOT the same as a standard 10, 12, or 14mm tap. I find a 12 pt socket that fits the tap and run the tap in and out (after starting it by hand, of course) with a 1/4" air ratchet.

Run the tap in and out of each bolt hole until a new head bolt screws in and out of the hole with 2 fingers. Find a blow nozzle that will fit into the bottom of the hole and blow it out frequently during this procedure and again before installing the head.
Be absolutely sure that each bolt hole is clean and dry before installing the head. If there is even a small amount of oil or water in the hole you run the risk of "hydraulicing" the bolt hole and splitting the block as you torque it down or later when you put the extra 1/4 turns on the head bolts.

[rabbid79]

I would definitely suggest using Hylomar on the head gasket too.  The VW factory uses a similar coating.  I have taken apart a Zero mile engine and seen the same tacky coating, although whatever they used was purple.  Hylomar is blue.