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-   -   B234 woes, Any solid cam buckets/lifters in the US yet? (http://forums.turbobricks.com/showthread.php?t=79266)

qwkswede 08-25-2006 08:51 AM

B234 woes, Any solid cam buckets/lifters in the US yet?
 
Hey guys. I have been cranking on my B23 w/16v head and turbo the last few days and haven't been able to start it. I was checking everything, fiddling with ign. timing. Checking the cam timing, and anything else I thought might be wrong. It never sounded quite right when cranking, like it was spinning too smoothly. Well, Now I think I finally discovered why my car won't start. Or at least I have a very solid theory now. The weird cranking sound was due to not having any compression. I put my compression gauge on every cylinder, turned the key, and I would sometimes get a tiny blip on the needle on the first compression stroke. But as soon as the motor cranked for more than a split second (think oil pressure here) I would get nothing on the compression gauge. The first thing I thought, was that I might have somehow bent some valves during assembly. But on all 4 cylinders? Unbelievable. But then I came to my senses and had a little more faith in myself to assemble a motor carefully without screwing up something THAT bad. What I am quite sure is happening is that the valves are hanging open once I get some oil pressure. The hydraulic lifters pump up to their normal spec when cranking and they start getting oil and are keeping the valves from touching the seats. Somehow, the machinist that performed the valve job on my head must have screwed up the valve stem height on the motor. He ground the valves, and the seats I'm sure, which sunk the valves maybe 20-100 thousandths? But maybe he didn't grind the valve tips down to set the proper tip height again? Maybe he was thinking they were adjustable somehow?

Darnit! In an attempt to salvage this problem without tearing the head completely out of the car again I was thinking of doing the solid lifter conversion. Has anyone pulled this off in the US yet? Can I get the lifters and shims somewhere? Even if I have to order them from sweden or something?

I have a feeling the right thing to do is get the head over to the machinist and let him fix it. Does anyone have a spec for the proper valve height on a B234?

740ATL 08-25-2006 09:17 AM

wish I could help.... but I'm pretty ignorant of the specs of the b234... I just assumed all the stock stuff worked and threw it all back together.... mine came straight from a JY car.

Did the lifters rotate freely in the lifter bores? I had a couple stick, but I removed and oiled the hell out of them...

can you rotate the cams by hand? (with the belt off of course)

Mike

qwkswede 08-25-2006 10:51 AM

Yeah, the lifters are new, and they rotate freely. I'll try to take some measurements tonight to see if the lifters are completely compressed when they are on the "back" of the cam lobe. I guess nearly compressed would be enough to lift the valves off their seats when the oil pressure pumps the lifters up. I'm not sure how these lifters are designed. With adjustable valvetrains on American things, you usually go to zero lash, then compress the lifter about .050".(1/2 turn). I wonder where I am with these volvo buckets.

thelostartof 08-25-2006 10:54 AM

aaron (ntrx) had the same kind of issues with his 16v... hence why his car is still not up and running.... he had his issue because hs MS took to much off the valves or something about them being cut wrong. he has tried all kinds of things and last i heard none of them did anything to help it run. tho read up in the 16v faq as i think he posted about the solid lifters needed

740ATL 08-25-2006 10:55 AM

do the lifters squish at all? I had a bucket of b234 hydraulics to choose from... I noticed some were rigid and some squishy when I squeezed them... (very non-technical terms) I'm going to say they squished about 3ish mm (1/8") when I squeezed them.... I chose the squishy ones.

I dunno.

I'm interested to see what you find.

Mike

qwkswede 08-25-2006 11:02 AM

Quote:

Originally Posted by thelostartof (Post 907466)
aaron (ntrx) had the same kind of issues with his 16v... hence why his car is still not up and running.... he had his issue because hs MS took to much off the valves or something about them being cut wrong. he has tried all kinds of things and last i heard none of them did anything to help it run. tho read up in the 16v faq as i think he posted about the solid lifters needed


Hey lostartofallthingsvolvo,
Would you be able to source the funny Renault lifters that people have talked about on the Forum elsewhere? I wonder how hard it would be to come up with those and a set of adjustment shims too. Sounds difficult.

Yeah. A normal valve job would sink the valves into the head a fair amount. You grind the valves a little, grind the seats a little, and Voila! the valve stem tips are closer to the cam than they are supposed to be. Now, a proper machine shop would cut the tips down to their correct height. If he new things were not adjustable. And I suppose the springs should be shimmed too so that the spring tension isn't lost.

thelostartof 08-25-2006 11:04 AM

i think i checked for aaron and couldn't get them .. tho if you can get me more part numbers i can sure try

but yea read up and talk to aaron as he knows a LOT aboutthis issue

it seems the only people with running 16v setups are those who leave the heads and valves stock(here in the US @ least) so there must be something the US shops are doing wrong when they work on these heads

MikeHardy 08-25-2006 12:13 PM

perfect opportunity to get the cams ground for more performance

Matt Dupuis 08-25-2006 12:22 PM

Quote:

Originally Posted by ravennexus (Post 907522)
perfect opportunity to get the cams ground for more performance

Probably the most desirable course of action - it would solve the compression issue and give more lift/duration if you choose it.

qwkswede 08-25-2006 01:24 PM

Wow, good thinking. Smaller base circle cams. Hrrrmmmm.

Who should I contact about this sort of nonsense? It might be more economical than finding a set of solid lifters and a complete set of adjustment shims that I would need.

I have only had custom grinds from guys like Chet Herbert. I don't know if he could do a set of volvo cams. But probably. I have some connections. I might pursue this.

milkyblue 08-25-2006 02:14 PM

I think there are more people out there with non-stock valves in 16v heads than you think-

Solid lifters would definately be nice

thelostartof 08-25-2006 02:21 PM

maybe its a case of the MS they go to just do not know what they are doing

NoSloVo 08-25-2006 02:55 PM

I wouldnt think it is a valve/lifter issue. Upon build-up the lifters rattle pretty good until the pressure builds up inside, like 10-20 minutes of the engine running. I dont think the machinist could have ground off that much but I guess it is possible

What timing belt/tensioner combo are you using? what pistons do you have? where did you source the head ?

Can you do a leak-down test ? If so try it with the cams out as well.

qwkswede 08-25-2006 03:17 PM

I"m running a Dick Prince tensioner setup with the Mitubishi Montero belt. Round tooth pulleys everywhere. There is no way its a valve timing issue though. Low compression from valve timing maybe. But not ZERO.

qwkswede 08-25-2006 03:50 PM

ONe of my first thoughts was. "Did I maybe reverse the intake and exhaust cams." But then after thinking about this. I realized that this would successfully make the engine pump air in the opposite direction. In the exhaust and out the intake. But there would still be some time when the valves are all closed and you would see compression on the gauge.

NoSloVo 08-25-2006 04:45 PM

... if you are sure you have the valve timing set up right and you didnt somehow bend the valves after install of the head, rings are good and head-gasket is sealed.... the isnt really anything else but the valve/lifter problem. Do a leak down with the cams out.

There werent a whole lot of 16v's coming through the shop I used to work at but still a few. I never heard of any problems after sending a head to the machine shop.

n xntrx volvo 08-25-2006 05:54 PM

do a leak down test. once as-is, once w/o the cams in. that will confirm or eliminate this as an issue.
get back w/ your findings, we'll take it from there.
note: solid lifters will make noise, not good for knock sensors.
-Aaron
fyi, it is possible to reverse valves also. but leak down it.

n xntrx volvo 08-25-2006 06:01 PM

also in my "16v propper clearance" thread theres a pic from a 16v lifter i tore up. it has a check valve that allows fluid to enter, but not go. this way at low rpm, the valves are quiet. once pumped up, they have to be pulled out and drained, or hope they slowly leak. you will not increase clearance any other way.
if the lifters spin (as listed before) with the cam on the base circle on a cyl, you have clearance.
also, gauvin can order shims from germany at the dealer if needed.

qwkswede 08-25-2006 06:18 PM

Leakdown, I can do. I guess that would help pinpoint the problem to the intake or exhaust side too. I may try that tonight. Good advice.

Here is the plan:
1. leakdown
2. check for any remaining travel in the lifters when on the backside of the cam by pushing down on the lifter.
3. remove the cams
4. leakdown
5. Reassemble without lifters, and Measure the distance from valve stem tip to the back of the cam, and compare that to the specs for the fully compressed and fully extended lifter.

n_xtrnx 16V turbo FAQ has some good info on the lifters.
Tappets = diameter 35mm/ 1.378"
total heigth 26mm/ 1.024"
distance to top of valve, unloaded 18.40mm/ 0.724"
loaded 16.15mm/ 0.636"
Springs, length unloaded, 43.0mm/ 1.6929"
length loaded 212-252N, 37mm/ 1.45669"
length loaded 600-680N, 26.5mm/ 1.0433"

Oh, and I found the fantastic thread with reground 16v cam info too.
http://forums.turbobricks.com/showthread.php?t=48558

I'll give American Cams a call once I am more sure of my problem and have some specs in mind.

What an annoying problem, though it might turn out good. I'm wondering how those grinds that Aaron made are working out performance wise.

n xntrx volvo 08-25-2006 07:00 PM

the lifters will "give alittle when at max travel. the main check is the rotating smoothly. it should spin very smoothly without binding.
the cam choice i've done is a good all-around. base circle can be set seperate of that.
one day i'll merge those threads into the faq, along with stage 2 work under way.

Unregistered 08-26-2006 03:43 AM

16V setting height
 
It is important to set the correct valve stem height for the 16V hydraulic lifters to work properly. The height is 49.4mm +/- 0.04 (=2 thou). This is measured from the top of a 30mm OD bar lying in the cam journals (which are 30mm ID) down to the top of the valve stem. I drilled 8mm dia holes in my bar so I could measure with the thin rod on a vernier micrometer from the top of the bar to the valve stem.
If you give this dimension to your cylinder head shop they can grind the valve stems to suit.
Dick Prince Ovlov.net

qwkswede 08-26-2006 07:47 PM

Well, bad news guys. I did a few more checks and the results don't seem good.

I tried a leakdown test with the cams removed, and I could only get 60-70% leakdown at best, depending on which cylinder. Just to be clear. I put in 100psi and could only hold 30-40 psi. Ive never seen such a leaky combustion chamber. I wanted to rule out any ring seal problems because the motor is 100% fresh and has never been fired, so I put a little oil into a couple of the cylinders to try and stop any ring gaps, and nothing seemed to improve. I guess the upshot, if there is any is that it looks like my leakage is isolated to the head and has nothing to do with the shortblock. Still quite annoying. I guess the head is coming off for sure. Bent valves? Bad valve job? What the hell went wrong?

n xntrx volvo 08-26-2006 08:11 PM

my quess is bent valves

qwkswede 08-31-2006 01:32 AM

More news. I pulled the head, and it looks perfect. I took it to my head shop (not the one with bongs) and he pulled a vaccuum on every port and the valves were sealing nicely. That was good news in a way. I still have no idea why I can't build compression, though I am ruling things out one at a time.

The only things left questionable are the rings. The motor has a fresh bore and hone. The rings came from the piston manufacturer and were filed to fit? Maybe, can't remember. I did measure the gaps at least and wrote down that the top and middle were both .018" gaps when installed. They might have been really close out of the box.

Could they be installed upside down? Wrong ring in the top groove? Would I get this problem by doing something silly like this? Or would it be somewhat normal for a motor that has never been fired leak this much? Doubtful.

OttoB 08-31-2006 07:28 AM

I would not blame rings. Head bolts maybe too long? Guiderings too tall ? How did head gasket looked like when you lifted the head. Compressed or not?


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