AQ170c Replaced Head gasket, now doesn't start, need some help

[heryrg2711]

Hey guys.
I replaced the head gasket and manifold gasket. Now the motor does not want to start, it turns over but doesn't start. When i increase throttle(to almost full), it seems like it almost starts but just doesn't quite get there. I do have fuel coming in. I'm not sure if there is spark, almost certain there is, will check in couple hours.

Do you guys think i messed up the timing somehow?

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Hey guys.
I replaced the head gasket and manifold gasket. Now the motor does not want to start, it turns over but doesn't start. When i increase throttle(to almost full), it seems like it almost starts but just doesn't quite get there. I do have fuel coming in. I'm not sure if there is spark, almost certain there is, will check in couple hours.

Do you guys think i messed up the timing somehow?

You have wires in the proper firing order on the distributor cap in a COUNTER-CLOCKWISE rotation, correct? Engine won't run if the wires are set up in a clock-wise rotation, ask me how I know.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

The wires are in the same order as when it ran.

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

The wires are in the same order as when it ran.

So I take it you never pulled them off the cap?

Was the distributor moved, or removed?
Have you physically checked for spark with a spark tester?
Did you properly set the valve lash?

 

[Don S]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

What procedure did you use for valve adjustment?

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I never pulled the distributor apart or out. I don't think i properly set the valve lash, i kinda twisted the pushrods while tightening the rocker bar, until pushrod resistance then tightened 3/4 turns.
Is there a "best" way to properly set the valve lash on these motors? I'm not too familiar with this adjustment, reading more about it now, so any info you provide will help.

I'm going home now and will check the spark, update soon.

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I never pulled the distributor apart or out. I don't think i properly set the valve lash, i kinda twisted the pushrods while tightening the rocker bar.
Is there a specific way to properly set the valve lash on these motors? I'm not too familiar with this adjustment, reading about it now, so any info you provide will help.

I'm going home now and will check the spark, update soon.

These engines are solid lifters, not hydraulically lashed (you don't set them up like a Chevy). Your current lashing technique is probably leaving the valves open a couple thousands, so the engine isn't building compression. You will need a set of feeler gauges, and the appropriate sized wrench and screw driver to set the correct valve adjustment. Valve adjustment is detailed in the service manual.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

So i figured out the problem. I took off the head cover and noticed that cylinder 5 pushrods are not even touching the rocker arm, took the rods out to notice that they are now bent. I guess rocker bar installation was not as good as i thought, i feel like an idiot :facepalm:

I'm gonna go to auto store and see if they have any rods for the b30 motor. Any info on how to PROPERLY install the rocker bar will be highly appreciated.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Anybody know where i can find replacement pushrods, 204mm length? Don't see any part numbers on pentaparts.

 

[RandyJ]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I assume you are rotating the crankshaft so that the cam has each push rod at its lowest point when you adjust them??????

 

[Don S]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Here is the valve adjustment procedures for your engine, it came from the same service manual I gave you a link to in one of your other posts.
You really need to read the manual for it to do any good.

You do understand what (on the compression stroke) means in the info below don't you?


Adjusting the valve clearance

The valve clearance can be adjusted satisfactorily
with the engine stationary, irrespective of whether the
engine is cold or hot. The clearance is the same for
both the inlet and exhaust valves. When adjusting,
use two feeler gauges, one ?Go? 0.50 mm (0.020")
thick and the other ?No-Go? 0.55 mm (0.022") thick.
The clearance is adjusted so that the thinnest gauge
can be inserted easily while the thicker one must not
enter.

6-CYL. ENGINE: When the piston in No. 1 cylinder is
at top dead centre (the compression stroke), valves
Nos. 1, 2, 3, 6, 7 and 10 (counted from the front) are
adjusted, and with the piston in the No. 6 cylinder at
top dead centre, valves Nos. 4, 5, 8, 9, 11 and 12.

 

[Don S]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I assume you are rotating the crankshaft so that the cam has each push rod at its lowest point when you adjust them??????

That is NOT how they are adjusted.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I understand the valve clearance procedure. I didn't install the rocker bar properly, i didn't rotate the crank when seating the pushrods.
On compression stroke meaning when the piston compresses the air and gets closest to the cam.

 

[RandyJ]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

That is NOT how they are adjusted.

Are you saying that at TDC the valves are NOT completely closed?

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Anybody know where i can find replacement pushrods, 204mm length? Don't see any part numbers on pentaparts.

Ebay, these guys;http://www.chapmanmotors.ca/volvoparts.html, or possibly an old shop that dealt specifically with Volvo cars. I went on a chase for a set of rods when mine bent after a mild hydro-lock. I ended up getting a couple from a local garage that works on Volvo's exclusively; http://www.merrymotors.com/. You do see complete sets of push rods come up every once in a while on ebay. A set for a B20 should work too.

Good luck.

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Are you saying that at TDC the valves are NOT completely closed?

TDC for cylinder 1 is not TDC for all cylinders. Finding compression TDC for each cylinder is not necessary.
What Don posted is directly out of the VP service manual, and hands down the easiest way to adjust all 12.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Thank you guys for the info. Got some used push rods from volvo 164. Going to install the rocker bar tomorrow and need to make sure i do it right this time. So when installing the bar how do i make sure that all push rods are in absolutely right place?
As i understand it, i need to put the 1st cylinder in TDC, put the pushrods in, put the bar in and tighten slightly. So after this do i just keep tightening the rocker bar evenly until the pushrods are very close to the ball studs, using feeler gauge on valves 1, 2, 3, 6, 7 and 10. Then i should put cylinder 6 in TDC and check the other valves. Is this correct?
To make sure everything is in right place can I rotate the crank and look at the pushrods to make sure nothing is stuck or did not fit correctly?

 

[PiratePast40]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Valve adjustment is performed at each individual rocker arm, not by tightening the rocker arm assembly shaft hold down bolts. Look closely and you'll see a screw with a jam nut on each rocker arm. You loosen the nut and then adjust the screw to get the go-no go clearance between the rocker arm and individual pushrods. Then hold the screw and tighten the jam nut. Measure again to verify that the screw didn't move. Repeat for each pushrod/rocker arm.

If you're not sure about TDC on the compression stroke, remove the number 1 spark plug and feel for air pressire with your finger. Do the same for number 6.

 

[heryrg2711]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

Valve adjustment is performed at each individual rocker arm, not by tightening the rocker arm assembly shaft hold down bolts. Look closely and you'll see a screw with a jam nut on each rocker arm. You loosen the nut and then adjust the screw to get the go-no go clearance between the rocker arm and individual pushrods. Then hold the screw and tighten the jam nut. Measure again to verify that the screw didn't move. Repeat for each pushrod/rocker arm.

I know this. I just wasn't sure how to put the bar in. I think i need to screw out the ball stud screw and then tighten the shaft hold down screws all the way, then adjust the valves once the shaft is in place.

 

[RogersJetboat454]

Re: AQ170c Replaced Head gasket, now doesn't start, need some help

I know this. I just wasn't sure how to put the bar in. I think i need to screw out the ball stud screw and then tighten the shaft hold down screws all the way, then adjust the valves once the shaft is in place.

Should not be necessary to loosen all the adjustment screws before installing the shaft. You will never get all the tension off the rockers, as you can't make it so the lifters are all down. Carefully place the rocker shaft in place, making sure that all the push rods are in contact with the adjustment screws. Torque the shaft to spec starting in the middle and working out wards. Then start adjusting the individual rockers using the method Don posted. You can find #1 compression TDC by observing cylinder 1 intake valve open then closing, once it closes look at the marks on the balancer and line up 0? with the pointer. Adjust valves listed in Don's post. You can find compression TDC with cylinder 6 in a similar way. The timing pointer may or may not line up exactly with the 0? mark on the balancer (can't remember), may be worth pulling the plug, and observing where the piston is in cylinder 6, it should be at the top of compression TDC to do the adjustment on the other arms listed by Don.