L16 first start advice?

[Negative Ghostrider]

I replaced the head gasket and timing gear on my L16 and it's time for the first start. I am honestly nervous as hell. This is my first "rebuild" and I'm hoping it doesn't all go to hell on me after many stressful hours, so I'm looking for advice on the first startup and break in. I'm guessing it's not as involved or critical as a full rebuild, but still. 

 

So let me see if I have this all right. 

 

Fill oil, put a little oil on the timing chain, cam and valve train

 

Pull the main plug on the distributor and crank for about 15 seconds to prime. Look for the oil light to go off indicating pressure. Check filter/carb for fuel. 

 

The coolant part confuses me a little bit. The rebuild book says to fill with water, open the drain and run a hose to keep it filling at the same rate that the water drains. But another says to fill with coolant via the high hoses to make sure that there's some past the thermostat, and leave the cap off and the drain closed, and add as the level goes down. I'd rather not flood my garage and driveway with water, and have to fill the system a second time, so the second option sounds nicer but I yield to the advice of the community. 

 

Connect the distributor, and light her up. Adjust the idle and run at 1500 rpms - OK. So I don't have a tach, and is this even necessary since I'm not breaking in new... everything? I will have to adjust both the distributor and the idle on the carb, correct? I feel like I should just need to run it long enough to make sure the thermostat opens and check for leaks, right? Or no? 

 

After shut down check belt tensions and stud torques. Check fluid levels and check again for leaks. If it all looks OK, take it for a drive, then check hot lash when done. 

 

Am I missing or wrong about anything? Thanks! 

[Crashtd420]

If you just replaced the head gasket and gears everything you described should be good.... break in procedure is more for new rings and cam.... 

Do you have a timing light?

It might have a tach built in... 

 

Good luck firing it up....

[datzenmike]

 

 

If all that was done was the timing gear and a head gasket then just start it up. You could dribble some oil over the chain while the valve cover is off but as soon as you start cranking the engine over, oil will spray on it.

 

Unless you are flushing the cooling system just fill the rad repeatedly until it won't take any more and leave the rad cap loose. The cooling system will automatically purge itself of air. After it has warmed up check that the level has dropped or not and top up. I would use 50/50  water antifreeze mix. Tighten rad cap.

 

 

If this was a complete rebuild with rings and bearings then fill oil pump and NEW filter with oil before installing and fill engine with oil by pouring over cam and timing chain from the top. If you used assembly lube on all bearings (as you should have) you don't need to prime the oil by spinning the engine with the coil wire off.

[Negative Ghostrider]

Thanks as always Mike. This sounds like way less of a hassle. 

 

I have 50/50 coolant mix and Chevron Delo (the place by my house didn't have enough Rotella). I used grease on the recommended surfaces like the eccentric cam for the fuel pump and the front seal but there was no mention in the book of greasing any bearings so I will probably give it a few juice free cranks just to be safe. 

[Negative Ghostrider]

Well she fired right up and seems to run pretty smoothly. I have some smoke on the manifold side so I'm guessing I need to re-torque all the exhaust manifold studs (ugh). Other than that I think I'm in business. No charge light so I'm guessing the alternator is working right as well. Thanks for everything! 

[Stoffregen Motorsports]

The cooling system can get bubbles in it. I run the engine without the radiator cap on it for a couple heat cycles (t-stat opens) before I install the cap.  How do you know when the thermostat opens? Well, for one, you'll see the coolant actually moving. Second way to tell is the radiator will get hot. It is best to do this on at lest a level surface, but if you can get the front of the car/truck up a little bit, this will help the air bubbles work their way out sooner.

 

Oh, turn the heater to hot when cycling the coolant. This also helps work out the bubbles.

[datzenmike]

Engine tilted up at the front so most bubbles work their way up and forward and the pump helps along stragglers. 510 and 521 thermostats didn't have a by pass and relied on a jiggle valve on the thermostat for circulation during warm up. This would let the air out when filling, though very slowly.

[Negative Ghostrider]

Thanks guys. I will take the cap off and lift the front a bit when I fire it up again after I retighten the manifold bolts.

[datzenmike]

DON"T!!!!! Tighten the manifold bolts!!!!! That is likely just oil from greasy hands when installing or oil dripped on it when the valve cover was off.. The smoke and will burn off in 5 min.

 

If not leaking coolant you're good. There is no oil on the manifold side that tightening anything will stop.

[banzai510(hainz)]

what MIke said.

Just wait till after it burns off in a day or so.

Must is residue whan when you pull the head head and git stuff over it.

[Negative Ghostrider]

Well I checked the nuts. They were all around spec. 12 lbs. It was hard to tell because you need wobble fittings and extensions to get to some of them, especially the lower ones with the curved washers that hold the intake and exhaust together. If they are too tight its not by much. Things smell a little exhaust-y but I think it's just from the tailpipe. I had the door open and the breeze was blowing that way. 

 

The smoke was indeed just burn off. It's done now and the smell is pretty much gone. I took it for a few spins around the block it seems to be running very well. I'm pleased. Smooth with good power. No issues when I floor it or come to a stop. It was definitely smoking white, with possibly some blue when I first fired it up but that's gone now. Must have been old crap and moisture in the system burning off. No visible exhaust now. 

 

My only lingering issues are:

 

I guess need to tune the timing and the carb a bit, I think. It seems like it's idling high but I don't have a tach or a timing gun. Once it's warm if I turn the main idle screw it gets a little rough for quite a while before I get near the stumble point. Advice? I hope it's not this crap knockoff weber. I think the choke is working ok because it fired up fine cold after I pumped the pedal before ignition, and it kicked down ok when I tapped it after some warm up. But it still idles high after kick down. 

 

It's running hot. I jacked up the front end and ran it again until the temp gauge was at midline before it drove it, so I'm hoping it burped out any air. I checked and all the coolant lines large and small were very warm and the heater was blowing hot air. So it seems like it's circulating fine. I have no leaks. I'm running 50/50 premix. It took the 6 quarts with no issues. The radiator itself is not hot, though. Could it be that I still have air in the system? Maybe I didn't jack it up high enough or run it long enough. 

Edited October 6, 2020 by Negative Ghostrider

[datzenmike]

No need to vent or try to vent air in the cooling system. The L series is already tilted up at the front, water fills from the bottom and any bubbles will rise to the top of the head. The thermostat is the highest point on the head and when it opens it will let out any air into the rad. They self vent. Just check the rad after it cools down and top up if needed.

[Negative Ghostrider]

3 minutes ago, datzenmike said:

No need to vent or try to vent air in the cooling system. The L series is already tilted up at the front, water fills from the bottom and any bubbles will rise to the top of the head. The thermostat is the highest point on the head and when it opens it will let out any air into the rad. They self vent. Just check the rad after it cools down and top up if needed.

 

Well something is going on. By the numbers I can't add much more and it's definitely running hot but the rad is cool to the touch. 

 

[bilzbobaggins]

I cant remember, can you install thermostats backwards on a L series?

 

And did the thermostat have the jiggle valve?

Edited October 6, 2020 by bilzbobaggins

[datzenmike]

The coil always goes into the engine. I don't think the cap will fit over it if in backwards.

[rosso]

Has anyone suggested the water pump? If there is no air in the system and the radiator is full, and the thermostat is good and installed correctly - then that only leaves the water pump as a possible culprit or completely clogged up radiator. It's such an easy part to get to it would be worth taking apart to look at. And if you take it out, why not put in a new one just because...

 

Head gasket failures often mean oil in the water and necessity of thorough flushing. I didn't see anything in your posts that described why the head gasket was replaced. My .02 cents worth.

[john510]

Is the fan belt on ? How can an engine get that hot and have a cool radiator ? 

[wayno]

Does the thermostat have an eighth inch hole in it, the jiggle valve is to let air thru, but not enough coolant can get thru that to work as a bypass, a stock L16 thermostat had a hole in it, but them thermostats were all sold out a long time ago, so you need to drill an eighth inch hole in your thermostat as a bypass, otherwise it may overheat and blow your head gasket.

[banzai510(hainz)]

try the used rad cap also.

and do the 1/8 inch hole as suggested.

I buy the fli[ up caps. instead of the ones that used for the overflow tanks

[datzenmike]

Look at the god damn gauge!!! It's reading hot so the thermostat must also be hot as both (temp sender) are in the thermostat housing. If the rad is cold then thermostat is not opening!!!! REPLACE THE THERMOSTAT!!!!!!! get a good one.

 

Doesn't need hole in thermostat as only the 510 and 521 L16s didn't have the bypass hose on the thermostat housing. The gauge is reading hot so there IS circulation of hot water.

 

Impossible for air to get trapped inside the cooling system. Air floats UP. It works it's way UP to the TOP of the head as you fill the system. The engine is tilted UP at the front and the thermostat is the HIGHEST place on the cooling system!!!! Any air collects there and if it can't get out it will when the thermostat opens and move UP into the rad hose, being pushed by the water pump, out to the TOP of the rad.

 

Can't possibly be the water pump unless the belt came off! The bearing can fail but you'd hear it and it would still pump or the seal can leak but it would still work.

 

When head gaskets fail oil cannot get into the cooling system. There is only one small opening for oil to feed up into the head to lube the valve train. It has a copper ring around it to seal. More likely water gets into the cylinder, works it's way down past the rings and into the oil pan.

[rosso]

Since no mention of why the head gasket had to be replaced, or what overheating issues may have been showing before repairs, all of us are just shooting in the dark so to speak. Until the OP gives more information, I agree with everyone to look at everything. Maybe everyone else knows the history of this car - mileage, etc. not me. I will be quiet and go stand in the corner.

[datzenmike]

Lets assume the head gasket blew because the head is now warped and the over heating problem is still there. The rad would be as hot as the over heated engine. It's reported to be cold so only way engine can be hot and rad not is if the thermostat hasn't opened.

 

 

When ever I come across an over heating problem the first thing is to shoot from the hip and put a new thermostat in. Testing is a waste of time. You have to part drain and pull the old one out and get a new gasket so why fuck with it? just put a new one in for the same effort. If this does not help then you have a known good used one for next time.

 

 

[Negative Ghostrider]

3 hours ago, rosso said:

Since no mention of why the head gasket had to be replaced, or what overheating issues may have been showing before repairs, all of us are just shooting in the dark so to speak. Until the OP gives more information, I agree with everyone to look at everything. Maybe everyone else knows the history of this car - mileage, etc. not me. I will be quiet and go stand in the corner.

 

Head gasket was replaced. That's where all this started. There were no overheating issues previously but it smoked. I drove the truck a few long stretches after I got it but it was smoking and timing looked to be off a link. When I tore it down it was obvious the previous gasket Jon wasn't done right. There was an indexing dowel missing, the fuel pump insulator was missing and there was some obvious leaking. I'm not sure about the mileage. It's at least a 4 owner truck. The Odo reads about 85k but I don't know how many revolutions that includes. Mike helped me figure out the head is not original. It's a W53, so it's been taken apart at least once. Nothing was warped by my eye with a straight edge when I put it back together. 

[Negative Ghostrider]

2 hours ago, datzenmike said:

Lets assume the head gasket blew because the head is now warped and the over heating problem is still there. The rad would be as hot as the over heated engine. It's reported to be cold so only way engine can be hot and rad not is if the thermostat hasn't opened.

 

 

When ever I come across an over heating problem the first thing is to shoot from the hip and put a new thermostat in. Testing is a waste of time. You have to part drain and pull the old one out and get a new gasket so why fuck with it? just put a new one in for the same effort. If this does not help then you have a known good used one for next time.

 

 

 

Thanks Mike. I'm not arguing with your logic, I'm just being skeptical because the thermostat worked fine when I removed it, and all the coolant lines are hot, including the one from the thermostat to the radiator. That's why I thought the core might be air bound. I'll throw a new thermostat at it next week. 

[datzenmike]

That's different. If the top rad hose is hot then coolant is flowing, though perhaps slowly.

 

Air can't block a rad it will bubble to the top and leave a space you can top up. Take the rad cap off and drain a half gallon out of the rad so the top of the tubes are exposed. Are they clean? or crusty with hard water scale? What I did was remove the rad and place front down with rad cap on and fill with a bottle of CLR which will dissolve hard water scale. Give it over night and rinse the next day. Good for drains with copper pipes abd solder so safe to use on brass rad with solder seams. I was busy and left mine for 3 full days with no ill effect.