After a (Very) long process, I am finally ready to start my truck. The engine has been completely disassembled,refreshed, and reassembled with all new parts, including camshaft. I have not ever started a "rebuilt" engine before. Any tips? Its an 82 351w.

One question I have is how to properly time the ignition prior to trying to start it. Do I just take the plug out of the no. 1 cylinder and turn the engine by hand until the cylinder is at TDC? How exact does this have to be? How will I know when its exactly at TDC? Then do I just install the distributor and go from there? After start up do I need to get a timing light and adjust it more? I have tried reading people's write ups and every single one is different on how they time it. I just want it to run as its intended to.

According to what I have read and the camshaft break in instructions, I need to leave the vehicle running for 20 minutes around 2000 RPM. Am I correct in assuming that I need to do this the very first time it starts up? Or can I start it, run it for a few seconds, then kill it to inspect everything and then start it and run for 20 minutes to break it in?

 

First who built the motor you or a shop? If a shop maybe they installed the dist on TDC so check with them to find out.
As for TDC, the timing mark will come up 2 times. 1 is TDC the other is 180* off and will back fire out the carb.
If you turn the motor over by hand with finger over the spark plug hole when on compression stroke of TDC your finger will be pushed off the hole. Line up the timing mark to 0* and that should be TDC.

The other thing is just before start up you should prim the oil system and get oil thru out the motor. Then install the dist and fire up motor.

You should run the motor 2000 to 3000 moving it up & down for 30 min. and should be straight thru from start up. Once you get the 30 min. in you can lower the RPM to it's setting.
For timing at start up I set it by ear where it sounds good. If the timing is too far retarded the manifold / headers can glow red.
Also make sure the cooling system has as much air out as you can. I like to drill a 1/8" hole in the flat part of the Tstat to let air thru when filling the system. I also get the front up as high as I can, radiator higher than motor to get air out. Leave the cap off the radiator and have a hose, fill the system with water for break in not 50/50, or more water on hand to top up when Tstat opens.

It helps to have 2 or 3 people to help. 1 in the car/truck watching the gauges, first start OIL PSI if none shut down. Then as it gets up to temp the temp gauge along with oil gauge. He/she is there to shut down if told to.
Another to keep eye on things like water/oil leaks and top up the radiator and if anything pops up to let you know.
You are looking over the whole picture, making adjustments to timing & RPM for that 30 min. After the first 5 min and the Tstat opens you are just keeping an eye on everything for that 30 min.

Good luck.
Dave ----

ps. when doing a break in on my drag race motor (open headers) I had the (old, worked good 2 weeks earlier) Tstat stick close and temp get up to 260*+. I had to shut it down, Let it cool off, I pulled the Tstat for the rest of the break in. Did it hurt it? Don't know but it ran good for what the motor was, put together with parts laying around.
Had to do the break in mostly because of new cam & lifters, bearings & rings not so much for me.

 

Okay thanks for the advice. I did all the work on the motor, but it was a couple of years ago. Its been stored full of oil since then. I drained it and installed all new fluids. When I built the motor, I did put the no. 1 cylinder to TDC and installed the distributor, but I just want to double check it to make sure I did it correctly, as I do not remember the process I followed and I want to eliminate as many variables as possible.

 

For first startup and breakin leave the tsat out completely and manually prime the oil pump to get oil throughput the engine. To do this remove the distributor and using a taped together socket and extension drive the oilpump in a counter clockwise direction with a drill until you get oil flooding the valvetrain. Now make sure piston #1 is at TDC on the compression stroke and stab the distributor so that the rotor is pointing at the #1 post on the cap. You can leave the cap fully wired.

 

^^yep what he said^^
If you have it set to #1 mark the dist. and pull it and prim as said then drop it back in lining up the marks.
Dave ----

 

Conanski is right on the money as always on motors. Follow his advice. Good luck on you motor.

 

What was your confidence level building your engine? Assuming that you did. I am just about to start a fresh build and deciding if I am going build it or should have an engine shop do it. I would love to have the pride of building my own engine but would defer to a professional if talked into it.

 

Not to high jack this post but how many books have you read and videos have you watched on building motors.
a motor is a motor and the principles are the same. Now all motors have "tricks" to make them better but the measurements and cleanness are the same.

You have to start some place, most start with lawn mowers and workup to the big stuff.
The other thing is how you feel on doing this. If you feel good then go for it.
Dave ----

 

To be quite honest, I am confident I can build my own motor, just being a wimp about it. I tore down diesel motors in my youth for a generator company so am familiar with the internals of an engine. Never assembled however I have watched build videos, got a copy of Rick Morris' ​​​​​​How to Rebuild Big-Block Ford Engines, and now just waiting on the donor motor to be pulled.

The OP seemed to be doing this for the first time so naturally I wanted to hear his experiences a bit.

Let us know how your break in goes!

 

James, you should be good to put one together, it's just reverse of taking them apart LOL.
Make sure everything is clean, eat off clean then clean it again. Take your time putting it together and look over books & videos as you go.

I would also like to hear how the OP makes out.

BTW the motors I put together were 2-v8's (Ford & AMC), 1-OVC I4 (Datsun) and many 3hp go cart motors were all built for racing and never had any issues.
Dave ----

 

Well, I got it fired up...and then the bad news came.

I have an oil leak in the back of the engine somewhere. This is clean oil. However, there was a leak up front, around the distributor (although may not be coming directly from there) that is milky. Like there is water in the oil.

I drained the oil from the pan and it is clean. I pulled the distributor and didn't see any milky oil. I suspect that the water has oil in it. Is this most likely a bad head gasket? The engine has been setting up for the last four years. Full of oil, no water. All new parts in the engine.

Also, the headers were red hot. Does this mean my fuel mixture is too rich?

 

From what I have been told is you are running too lean when your headers get red hot. Mine are but I haven't messed with it. Need to get my timing in order since my idle is stupid high, about 1300rpm.

Couldn't give any advice about the milky oil except to check the compression to see if you have a bad gasket. Did you drop the motor into your truck already or do you have it on a stand. The latter would be easier to take the heads off if you do get low compression numbers.

Good luck and keep at it!

 

Rear main seal. 2 piece, correct? That would be my first bet. Unless it was leaking down from higher up above...

Is the leak up front between the intake and the block/heads?

 

I'll have to investigate further where the leaks are. The front one looked like it may be the o-ring on the distributor. The leak in the back I am not sure. It may be a bad head gasket and coming from between the head and the block. I guess it could be the rear main seal as well. Although I think I may have had a one piece Rear main seal. Maybe I am mis-rememering. It was quite some time ago.

 

Back in high school when I bought a junkyard motor to replace the 4.9L I blew a hole in had a leaking rear main seal cause it dries out I think if not mated to a transmission? Either way, I didn't know about that at the time so I had a nice leak for the next couple of years till I sold it. I know now and will be all over that when I build my 460.