aackshun

iTrader: (3)

Have a 3.0 timed VQ35?

Sweet.

Have any problems down the line a year or two? Let me know, my mechanic came across some very interesting findings after having both motors apart and may have solved a problem that he thinks all hybrid swaps have with skipping time.

Question is... Have you had a hybrid swap done? How long has it been running? How many miles (guesstimated) was on the motor?

Thanks!

McSteve

iTrader: (3)

well how about you tell us about that problem so that the people about to do it are able to avoid that problem.

BigLou55

iTrader: (6)

this

mightyMax95

iTrader: (5)

and spoil the fun? nahhhhh

95naSTA

iTrader: (10)

Did it in 06 or 07. It's been apart for skiped timing and oil leaks. Maybe 50k or so on it.

aackshun

iTrader: (3)

^ Thanks!! any one else???



Hrmm... Too easy.

I'll play ball....



But the next off topic response will get flamed, fair warning.

I did not want to drop this and start more unfounded .org rumors on stuff, but since you MUST know.....
The Secondary Camshaft tensioners seem to be the cause of the problem, they have extra oil channels that are meant for the 3.5 but not the 3.0, my mech discovered this while trying to figure out what all of the extra channels are for and why they are there after hours of fsm diving and comparison.

Now, if you have any other questions, stfu and wait, we don't want to speak pre-maturely, this is just an assumption that's made because of a local w/ a hybrid swap here has skipped time 2x now, and I've heard of other motors loosing time too.

IF what we think is true then we should hear more cases involving other people suddenly loosing time in the motor, after some time has passed (one year or two).

THEN! I will go into gross detail on what we think is happening and what's going on.

nselca2

iTrader: (4)

This is interesting. I think my 3.5 swapped maxima skipped a tooth. Ive had a couple people (nissan tech and a well known forum member on the board) check out my po300 misfire code and it has all been pinned down to timing being off. It misfires intermittenly and has been lacking slightly in power from when I first had the car. Looking forward to seeing your resolution to the problem.

Nealoc187

iTrader: (23)

i did my swap in late 07. it's got probably 25-30k on it since the swap. the motor i believe had like 80k on it when i put it in. I have no reason to believe it has skipped time.

aackshun

iTrader: (3)

Hrmm hit or miss in here, I see... I see.... So far so good w/ the responses, keep them up, thank you guys!

If you can recall can you also tell me which secondary (camshaft) tensioners you guys used??

grey99max

iTrader: (12)

Troublemaker... My first 3.0/3.5 was a few years ago (too lazy to look it up) and it always had some timing chain slap at idle, but it never changed timing and ran purdy good until I burned out an exhaust valve on the last track day of the year. I just re-used all the old 3.0 chains and tensioners- had 60K on it, I think. Want the old engine? I've got another head for it....

The new one has all new 3.0 tensioners and chain guide parts, and it's never skipped timing either. With the ZK2 cams and dual springs, it has every excuse to jump something. It was hard to turn over on the stand with a breaker bar without plugs installed. It has over 100psi oil pressure on startup and a little less hot. I don't think it has an oiling problem...

maxima.713

iTrader: (7)

The local he is talking about is me. Mine has jumped timing twice! The first time it jumped after having the swap for about a yr. Got another 3.5 and it jumped time again after about 2 yrs.

aackshun

iTrader: (3)

Ok, I see where this is going now....

I would still like responses from guys who have had issues w/ timing but now can you guys tell me what you used for your swap (both of those who has had their swaps working for years, and those who has had their swaps loose time)

3.0 or 3.5 Secondary Timing Tensioners (Camshaft Tensioners) and 3.0 or 3.5 Main Caps?

Thanks!

NmexMAX

iTrader: (22)

Is it losing timing because of a loose timing chain, or am I mistaken.

I kid I kid.

ajcool2

iTrader: (43)

We finished our swap 09/09 and ran it until 10/10. The engine didnt skip timing and is still functional today. We used the 3.5 secondary tensionors and 3.0 main. When we put it back together we are using the same.

98MistSE

I finished my hybrid swap back in October '09. The 3.5 I used was from an 04 with about 70,000 on it. I used my original 3.0 main and secondary timing chains but, installed a brand new (old style) main tensioner (had one for years but, never installed it). For the secondary tensioners, I left the stock 3.5 ones on there. I now have about 10,000 on the swapped engine.

My old main chain used to rattle at idle, but this one has been quiet since the swap. Also, if it helps to add, at cold startup, my oil pressure is about 90 psi and drops down to 30 or 40 psi once warmed up. On the highway, once it is warmed up, at about 3000 rpm, my oil pressure is about 60 psi.

Hope this helps you out.

Chris

t6378tp

iTrader: (69)

put about 30k miles on my swap timing was fine till I bent a rod boosted

aackshun

iTrader: (3)

3.5 Secondary tensioners and main cap I'm assuming?

Crusher103

iTrader: (10)

hmm, those secondary chains are on pretty tight so i wouldnt think they would be much of a problem with skipping timing even if they didnt have good oil pressure, but i the best solution would be use all 3.5 tensioners instead of mixing up with the 3.0s tensioners. problem should be solved.

t6378tp

iTrader: (69)

3.5 secondary/3.0 guides with a new revised 3.0 main and chain
also don't forgot to enlarge the hole for the oil drain and drill out a hole on the inner cover

aackshun

iTrader: (3)

That's the proposed problem, the 3.5 has extra oil channels that aren't used on the 3.0, which over time causes it to loose pressure. Just like with Maxima.713 loosing timing 2x, and one other person, I want to narrow it down to this...

Anyone that has driven considerable amount of miles or done considerable amount of abuse to their swap? It seems like so far the working ones have been treated nicely, and I know 713's was not treated nicely at all (in a redlining aspect, not maintenance), and I will abuse the **** out of this one too.....

Crusher103

iTrader: (10)

Yea this is why im saying the solution will be use the 3.5 tensioners. Which is what most people on here that do 3.5 swaps do thats why we dont hear much about people skipping timing i assume. The 3.0 tensioners also fit on the 3.5 and vise versa.

Something you would know if you tore down the motor yourself but then again this problem would have never been addressed. You dont have to use the 3.0 secondaries, and im not sure what the pieces is that holds down the camshaft but also that doesnt change during the timing swap so there is no difference in the oil channels thus eliminating said issue. The only time this could be an issue is either using 3.0 secondaries or those people who want to retain their 3.0 valve covers. Unless you are talking about the actually timing cover blocking an oil channel or something of that nature.....

i might have an issue because of my SSIM and valve covers on the 3.0 but we'll see how that pans out.

Kevlo911

iTrader: (36)

I've read of maybe 10 timing chain skips, and i've read/seen over 100+ swaps.

Not saying your guy is wrong, but i don't think its common at all

MarcL

FWIW, I am on engine #3..

1st one blew a piston (running a blower).
2nd one lost a thrust bearing, I replaced all of the main/rod/thrust brearings, but then had low oil pressure.
on the 3rd engine now, just installed it, and this one had low oil pressure too (once it is warmed up).

We found the same thing, that the 3.5 cover has the extra oil passage, and it seems that passage is what gets oil to the intake cams. I was wondering if our conclusions were wrong? or if others were having issues too.

Either way, I am not convinced this is the source of the low oil pressure issue.

MarcL

Traced all of the paths for oil last night. Best I can tell, the oil feeds that are missing from the VQ30 timing cover are JUST for the variable cam control.

The oil passes through the tensioners, but does not dive them. It is just a path to the solenoids. With the solenoids at rest, the oil is dumped in to the intake cam (but it is not the only feed to that cam). When the solenoid is activated, the oil is diverted in to the timing cover to the cam adjuster.

Based on that, I see no reason to feed oil in to those ports.

Maximeltman

iTrader: (11)

Are you sure that the oil doesn't keep the tensioners more tense?

MarcL

It does not look that way to me. There are 2 oil passages that go from the head in to the tensioner. The one (and only one) that pushes oil in to the tensioner is NOT the same one from the timing cover. That seems just like a pass-through to the solenoid.

Maximeltman

iTrader: (11)

Where's the second one?

MarcL

If you take the tensioner off the head, you will see 2 holes under in. Inspecting the tensioner itself, the oil hole that comes in the bottom and out the top just passes through, it does not have any impact on the performance of the tensioner.

Maximeltman

iTrader: (11)

The solenoids do indeed divert the oil when it's needed for the vtc, but I'm pretty certain that the oil doe not merely just pass through the chain tensioners, I think it also primes them thus making them more tense. Can you post pics to further sustain your findings?

MarcL

I will check my work, but what I did was put compressed air in to the "pass-through" hole, and blocked the other side. No air made its way in to the tensioner.

When I put air in the 2nd hole, it all came out the tensioner (with the piston/spring removed).

Maximeltman

iTrader: (11)

I just traced the oil pathways again, because again, engine is disassembled. What I found is that oil passes through the 3.5 tensioner, into main cap, into solenoid, then back through the main cap to the head, then into intake cam, then out from exhaust cam, back into main cap, then through head again, finally up to the second hole in the 3.5 tensioner. This proves that the 3.5 tensioner does indeed get primed and pressurized. I have pics to show the flow.

MarcL

To me that does not make sense. How can the oil flow from the intake cam to the exhaust cam? The way I see it, oil is coming direct from the pump to both cams, and the tensioner. The oil that flows from the solenoid/cap back to the intake cam is just a place for the excess oil to escape the solenoid when it is "off". It is not the primary source of oil for the cams. If it was, then everyone running this conversion would burn up the cams quite quickly.

Once the oil hits the cam, it is out of the pressurized side of the flow.

Maximeltman

iTrader: (11)

I used pressurized air to see where the oil goes, I know what you mean though, but I'm pretty sure of it. I will post up my further findings.