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jimcub
30-10-2012, 05:36 PM
The 2 replacement heads I have tried have both been completely different, I have a 040101375 which is not a VW marked head and the replacement is a 040101375 which has VW stamped on it

But the head chamber is about 10mm difference in depth, mine has a deeper chamber. :confused1:

Pics will follow in the morning, but is there a site that explains all the different types. :giveup:

MicksRedNova
30-10-2012, 08:19 PM
Jim
If you Google the numbers you will find numerous descriptions. The number appears to describe a Brazilian made head. Maybe one has been modded by someone. Both headson mine have different numbers and the engine runs fine.

Mick

letterman7
30-10-2012, 09:30 PM
I just ran into that with my engine. Like Mick mentioned, they could be from anywhere. The important thing is that the head CC's match - in your case they don't, so that could cause some issues with the engine. Your option would be to machine the odd head out to match the CC's of what you already have (or vice versa) or find a pair of matched heads. It'll run mismatched... but it isn't "good" for the engine.

Peter
31-10-2012, 12:31 PM
With the head off and valves still in place, fix horizontal using spirit level with chamber facing up.

Cut piece of Perspex to cover chamber and drill small hole in centre. (This eliminates the ‘doming’ effect of surface tension)

Smear grease over head face as a seal and firmly apply plate.

Fill a 60cc syringe with thin oil. (Diesel is good)

Fill chamber via hole from syringe until oil is at hole and no bubbles.

Check syringe to see how much has been used, e.g. (60cc less 9cc left in =51cc, (stock) gives a compression ratio of 7.64:1), that's your head CC, repeat on all 4 chambers.

Adjust; if one head has both chambers the same but larger than the other head then a skim will reduce the volume of both and match it up with the smaller head then you can fine tune each chammber so all 4 are the same to the exact cc.
OR if the larger chamber is 51cc or less (if you have the patience and skills with a Dremal) gradually removing materiel from the smaller chambers to enlarge the CC until all 4 match, as I have done, or Skim to higher CR if you want. For example, if largest head is 53cc and you open all up to 53cc then skim head to give 51cc or better CR.

OR buy a pair of matched 041 heads with stainless swirl valves and lead free hard seats, good for at least 10hp over standard and double std with a lot of port work, etc.

Page 112 of the DellOrto tech book gives all the options.

The main thing is to get the ports sizes and head chamber volumes the same on all four cylinders.

p.s. pair of 1600cc heads on Ebay for £100 in Twickenham
New ones about £300 to £400 a pair

Alzax3
31-10-2012, 05:44 PM
"Check syringe to see how much has been used, e.g. (60cc less 8cc left in =51cc,)"

Am I missing something in the maths there, Peter? What's happened to the other 1cc?

Peter
01-11-2012, 11:43 AM
Nit picker :tongue: OK amended. dizlexier rules KO

Alzax3
01-11-2012, 11:56 AM
Nah, I was genuinely checking I hadn't missed something in the calculation! (ignore 1cc for surface tension or something.....)

jimcub
01-11-2012, 06:57 PM
Got pics on phone so will load up, the difference in the heads is quite a lot. I will measure the difference in depth of both heads, thing is this may not cure the original fault.

jimcub
08-11-2012, 08:07 PM
right finally got round to uploading pics

Not great done on phone as I shred cameras, something about static and me I think.

First pic is both heads

http://i666.photobucket.com/albums/vv26/jimcub/nova%20pictures/headident01.jpg

this is my original head

http://i666.photobucket.com/albums/vv26/jimcub/nova%20pictures/headident03.jpg

this is a head with same numbers stamped on it but the depth to the valves is much shallower.

http://i666.photobucket.com/albums/vv26/jimcub/nova%20pictures/headident02.jpg

So what's going on here :please: you know my expertise is not as great as some on here. :stupid:

MicksRedNova
12-11-2012, 10:48 PM
Jim

Bit hard to tell from the pics but I think these are the same size. I reckon the key is that the groove (that the barrel sits in) is a different height on each head. If you compare the distance from the barrel groove to the valve faces I think you will find they are the same.
If you want to do a 'cc' check you will need a plate that is the same diameter as the outside of the barrel to sit in the groove of each head. A quick check could be to put a plate in the head and poke something in the plug hole and measure the depth.

Mick

letterman7
13-11-2012, 12:57 AM
Huh... I wonder if one of those is off a T3 engine. Not only are the combustion chambers different, but the valve geometry and shape as well as the spark plug alignment. It also may be that one is an early 1300 head and one is a later 1600 head... but I'm guessing here. Still, the best way forward is to find a pair of matched heads.

Peter
13-11-2012, 11:34 AM
At a guess I'de say a 1300 and a 1600. If I did my measurments on the photo correctly the valves are bigger on the lower head.

Valve size will sort it out.

Inlet valve head sizes;
1192cc (1200) 12.4mm
1258cc (1300) 13mm
1493cc & 1584cc (1600) 14mm

Exhaust:
1200 & 1300 = 11.8mm
1500 & 1600 = 12.6mm

jimcub
13-11-2012, 12:30 PM
Hi thanks for the answers the one with the smaller valves is the head i have, the biggest difference is the measurement from the surface of the cylinder on mine is 15mm on the other it is 3mm, Also mine has short reach plugs and the other will take long reach plugs, was stated on advert to be a low compression head. But the sites i have looked at al show a low compression head the same as mine, so i would like some sort of a reply to give to the bloke i bought it off.

MicksRedNova
13-11-2012, 02:17 PM
the biggest difference is the measurement from the surface of the cylinder on mine is 15mm on the other it is 3mm, Also mine has short reach plugs and the other will take long reach plugs

I think the distance from the surface of the cylinder head to the bottom of the chamber (or flat of the closed valves) is a red herring. As the barrel sits inside the head casting it is the measurement from the bottom of the groove the barrel sits in to the chamber that matters. The short and long reach plugs could also be related to the thickness of the alloy head, try measuring the depth of the threads.

Mick

jimcub
13-11-2012, 06:32 PM
Forgot head stops about 1" from the barrels when slid down the studs, won't go any further however it is waggled

jimcub
23-11-2012, 04:24 PM
well i got an exact match from vwheritage was in the clearance section with a broken rocker stud, never been run so it said and it's all nice and clean and unused, so a quick lap and it should be ready to fit :crossfinger:

jimcub
23-12-2012, 06:39 PM
Head cleaned and lapped, damaged stud removed and all ready to go back on, just have to find a clear time in the Xmas schedule to start. Good job the garage has a nice gas heater in it and a carpet floor, yes I found a good use for all those off cuts beats cold concrete anytime.
Just hope 2013 is better than this year has been, happy hols folks. :groupwave:

jimcub
18-02-2013, 04:53 PM
Blimey it's February already

Well had the engine built up for me ( old age ) and fitted, nnnnnnnnoooooooooooo!!!!!!!!!!!!! Same fault. Fires on 3 cylinders.
New head and new valves, new electrics all that's left is the cylinders themselves, can't get my head ( no pun intended ) round this.
May take to a vw nut at our local mot place for a pressure test just to check before I delve further, as have to have my mate round to do all this now.

MicksRedNova
18-02-2013, 07:07 PM
Jim

Just in case - have you checked the inlet and exhaust manifold/tubes on the faulty cylinder? Short of a blockage I can't see what else it could be. I assume you have already done a plug, lead and distributor change.

Mick

jimcub
18-02-2013, 07:48 PM
Hi Mick plugs leads and fuel all accounted for, the exhaust heats up on all cylinders. I wonder if there is a problem with the cylinder or piston, as that was the one that had the reoccurring hydrolic lock problem due to water ingress. Now sorted due to having a garage to store it in.

MicksRedNova
18-02-2013, 11:11 PM
Jim
I'm confused. If all exhaust headers are getting hot why do you still think its only firing on three cylinders?

Mick

Peter
19-02-2013, 10:51 AM
Firing order? 1 (at 5 o clock) 4-3-2 clock-wise
All any engine needs is compression, fuel at about 16:1 and a spark at the right time just before TDC as a rule. all that in place it WILL run. I say firing order as it has been known to have leads on wrong and the engine will fire up but it is acually running on 2 plus 2 x 1/2 firing on exhaust stroke not compression stroke, so exhaust gets hot but provides no power, if you get what I mean.

jimcub
19-02-2013, 11:30 AM
No power and it sounds like fire ring on 3, put your foot down and there is a lag and the power is not there even with throttle. Nothing had changed when it suddenly went like this , so confusing.

Peter
19-02-2013, 01:31 PM
The chances of a bent rod due to hydraulic lock are slight but not impossible, The only way is head off (again) to check the compression hights on number 3 and 4 cylinders to see if the piston is lower by a fair bit on number three compaired to number 4 (I happen to have a spare set of 1600 rods from when I fitted the H section rods), lucky it is possible to change the rods with just the barrels off, in this case number one and three.
If it is getting hot on the exhaust manifold then it is firing but not at the correct time. possibly at BTC, 180 degrees out on exhaust stroke.
I would go back to basics and start by checking the dizzy notch in rotor lined up with notch in dizzy case with number one, (right, next to clutch) at TDC compression stroke, gapped correctly, cap on, check lead positions firing order, sometimes the obvious just slips past, number one at 5-o-clock, number four at 7-o-clock, number three at 11-o-clock and number two at 2-o-clock.
Plug caps, plugs. if all that checks out tick ignition, move on to valve clearances, all OK, move on to carb setting, all ok? compression test and if that's OK it's an alian living in your engine.

MicksRedNova
19-02-2013, 08:17 PM
Jim
I concur with Peter's advice below. Go back to basics and double check everything. I had the mis-firing engine thing after mis-reading the labels I put on the plug leads :oops2: After checking all the unlikely things and scratching my head for days it came to light when I was swapping leads to a new dizzy - doh! and kicked myself.

Mick

jimcub
24-02-2013, 06:10 PM
My friend and I did double check the electrical bits, all seemed to be in order. We fired it up and still the same, so I guided him in stripping it down.
Found on member 4 cylinder thick black oil on top of the piston and the head, number 3 was dry. I will post pictures late on.

this is the oily piston
http://i666.photobucket.com/albums/vv26/jimcub/WP_000105_zps9327c8d4.jpg

This is the dry piston both run for about 1 minute
http://i666.photobucket.com/albums/vv26/jimcub/WP_000104_zps2d6bf401.jpg

Think it could be a piston or cylinder problem, I have a set of 1600 B&P ready to go in if needed.

MicksRedNova
24-02-2013, 08:22 PM
Jim

Did you test compression someetime? It sounds like you may have stuck or broken rings on number 4 letting oil in which will foul the plug. Or you could have a crack in the piston crown.

Mick

jimcub
24-02-2013, 08:36 PM
I will have to strip and clean I think

Peter
25-02-2013, 12:52 PM
Or it could be a valve stem seal and unless the carbon / oil is very thick, you have two differnt pistons there going by the lack of a circle.

jimcub
25-02-2013, 05:17 PM
leaned the piston and cylinder and there is light marks on the side (not scratches ), looks like the rings were not touching as though the cylinder was misshapen. The oil ring did not seem to have much spring in it either

The spare set i had I cleaned one set up and am confused a bit as usual, the pistons I measured and all measurements are the same as was the cylinder bore.
The spare piston will not slide easily in the original cylinder, that's without any rings on.
the spare cylinder has 241-101-302 cast into it which I cannot find anywhere.
the spare piston has 85.98 and 1761 stamped on the top, so is the spare lot 1600 as it was sold to me as or a different lot.

:cursing: :cursing: :cursing: :cursing: :cursing: :cursing: :cursing:

my friend who is doing all this is very confused as he is not a vw person, if he had hair he would not by now i can tell

MicksRedNova
25-02-2013, 07:56 PM
Jim
Here's a useful link that includes piston sizes http://www.aircooled.net/vw-performance-engines/

I found the sizes on the crowns of my pistons but it is hard to see - needs polishing.

You could have an ovalled cylinder due to overheating.

Mick

Peter
26-02-2013, 12:55 PM
Chuck the 1600 B&Ps on and that will be one less to worry about.
85.5 x 69 is std 1600cc (1584cc) The only larger kit without machining is the 1641cc kit like wot I got.

bushboy
26-02-2013, 09:18 PM
The only rule of thumb I can give you is that for air cooled engines you need 4 thou per inch of bore on the ring gaps.

It's in thous cause my dad, who told me back in my 2 stroke days is a POM & uses OLD measurements.

Bushboy

jimcub
26-02-2013, 09:25 PM
When we used the new torque wrench the readings in the book were different from what was on the wrench, still can't find anything that will convert from on to to'ther. Ah well that's progress and unification for you.

Peter
26-02-2013, 10:41 PM
I find torque settings come in five values, finger tight, a wrist full, A good elbows worth, get yer shoulder into it ans both hands to the welly bar. :facepalm: I find cylinder studs are elbow tight.

jimcub
27-02-2013, 04:20 PM
I find torque settings come in five values, finger tight, a wrist full, A good elbows worth, get yer shoulder into it ans both hands to the welly bar. :facepalm: I find cylinder studs are elbow tight.

Is that the metric values

jimcub
27-02-2013, 04:25 PM
I slid the spare cylinders I have over the studs and it went right home into the block, so I wil havemy mate replace the oily piston/cylinder with one of my spares, then build up the engine and try. :crossfinger:

Just have tomwaitmuntil he is free.

Peter
27-02-2013, 07:22 PM
I find torque settings come in five values, finger tight, a wrist full, A good elbows worth, get yer shoulder into it ans both hands to the welly bar. :facepalm: I find cylinder studs are elbow tight.

Is that the metric values
Newtons (bitter)

jimcub
27-02-2013, 07:46 PM
Just have tomwaitmuntil he is free.

Wish this I pad would stop confusing the space bar with the m button, my fingers don't alwaysmwantmto go,that low :oops2: :sorry: