Carburetor & Valves Adjustments (1 Viewer)

[AYM707]

Model : FJ45 1983 - stock

I noticed recently that I had alot of engine vibration, maybe low speed, and the exhaust fumes were excessive. There's no smoke. Thought it was time to re-adjust the carburetor using lean median method.

Set-up
- Digital tachometer connected to the coil
- Vacuum gauge on the inlet.

This is what it was like before I started. Engine was already warmed. Water bottle is my vibration meter. Getting 14-15 in Hg vacuum and speed is roughly 600-650.

Closed the idle mixture screw, and then turned out 2 turns. (at 1 1/2 engine cuts out). Then slowly increased my idle mixture screw to max RPM and reduced the speed back down to roughly 680 RPM. Did that a few times; this was my final...

Tried to set the speed at an average of 690 RPM and was getting about 19 in Hg; but still had engine vibration. (I wanted to upload the videos but could not figure how to do that? Does Mud not allow videos?).

I can hear my rockers, so thinking I have to tighten them. But I'm unsure on the following :

• How do you turn the engine, for drop-dead-center? What socket size fits the main bolt?
• What am I looking for in the window; is it a painted mark? Does it only identify cylinder #1?
• Before adjusting the spacing, do I have to make sure each piston cylinder is at drop-dead- center? How do you determine the d-d-c points for the other cylinders?

Appreciate some guidance.

 

[Pighead]

I usually do my valve adjustment and timing before i do the fine tuning, but I also have to go back and fiddle with timing while adjusting the carb.
1) I forget the socket size, I use a crank handle. Plenty of other ways to turn the flywheel.
B) It's a shiny BB sized BB looking silver bit. Not painted unless a PO did it. Also a fine line nearby, probably not shiny.
III) both #1 AND #6 are at TDC when you see the mark(s) which can lead to confusion, hilarity usually ensues.
When you are at TDC #1 compression stroke you can adjust half the valves (123579 off the top of my head). Rotate the crank one entire rotation, to the marks, adjust the rest.
Probably better write-ups in the FAQs.

 

[charliemeyer007]

I'd rather hear the valves than burn them from being too tight. Doubtful your valve adjustment is making it run ruff unless they are really clattering. Go buy a tankful of premium at different station and run that threw. How are your spark plugs for a clean square gap, what color are they and does your ignition system make them throw a nice blue/white spark. Go out on a dark moonless night, open the hood and have someone start it while you look for dancing sparks off the wire.

 

[AYM707]

I usually do my valve adjustment and timing before i do the fine tuning, but I also have to go back and fiddle with timing while adjusting the carb.
1) I forget the socket size, I use a crank handle. Plenty of other ways to turn the flywheel.
B) It's a shiny BB sized BB looking silver bit. Not painted unless a PO did it. Also a fine line nearby, probably not shiny.
III) both #1 AND #6 are at TDC when you see the mark(s) which can lead to confusion, hilarity usually ensues.
When you are at TDC #1 compression stroke you can adjust half the valves (123579 off the top of my head). Rotate the crank one entire rotation, to the marks, adjust the rest.
Probably better write-ups in the FAQs.

Thanks @Pighead Can you take a picture what it should look like? at TDC. Appreciate it

 

[Pighead]

Thanks @Pighead Can you take a picture what it should look like? at TDC. Appreciate it

No. there are 3 or 4 things to look at to make sure you are at TDC #1 and I don't feel like taking off my valve cover today. here's a pic of the BB and the line you're looking for. Mine's blue because it's my favorite color.
since you're new at this, you'll also want to look at the rotor and rocker arms and piston tops through the sparkplug holes.
probably a lot more pictures and detailed steps in the FAQs.

 

[AYM707]

No. there are 3 or 4 things to look at to make sure you are at TDC #1 and I don't feel like taking off my valve cover today. here's a pic of the BB and the line you're looking for. Mine's blue because it's my favorite color.
since you're new at this, you'll also want to look at the rotor and rocker arms and piston tops through the sparkplug holes.
probably a lot more pictures and detailed steps in the FAQs.

View attachment 3542040

View attachment 3542041

Thanks @Pighead - I'm going to look for it this weekend. Will try placing it in 4th gear and then turning the rear wheel technique to turn the engine.

Separately, I've uploaded the video of my adjustment attempt on the IH8MUD facebook page. Link below (not sure if this link is working)


I would appreciate any comments / observations.

 

[77mustard40]

I usually do my valves when changing plugs:

1. Motor hot - drain oil and pull the plugs​

2. Replace drain plug so you don’t make a mess.​

3. Remove valve cover, 4th gear and truck on a flat surface then rock the truck to TDC​

4. Adjust valves per FSM​

5. Rock 180 360 degrees to timing mark again​

6. Adjust remaining valves per FSM​

7. Replace valve cover, gap and install new plugs.​

8. Replace oil filter, refill with oil of your choice.​

9. Start and check/set timing​

10. Adjust idle and any other carb adjustment if required.​

​

Final step 7 = beer, your done​

 

[AYM707]

So tried the raise the rear end & manually rotating the tires, while in 4th gear technique. That was a waste of time. So then thought I would try what I saw an old mechanic once do.....turn the engine using the radiator fan. Disconnected the battery & coil; and very slowly managed to turn the engine using the radiator fan hub. It was a piece of cake; much easier than I thought and gave me a great view of the window.

so found the BB but did not find the line. Now I understand that the BB is TDC for piston #1 & 6; and I'm supposed to turn it 180 for TBC of the other pistons. But how do I know I have turned the engine 180 degrees?

I did also see these "painted" marks...not sure if they are 180 markers?

I'm going to take the valve cover off this weekend to start identifying inlet / exhaust valves. I will also try to look through the plug holes.

 

[Pighead]

and I'm supposed to turn it 180 for TBC of the other pistons. But how do I know I have turned the engine 180 degrees?

NO. You turn the crankshaft 360 degrees. Until the BB and mark come back into the window.
The camshaft (and dizzy rotor) will turn 180 degrees because gears

 

[AYM707]

So I found the line; its not very visible, but was half a turn further from the BB. (roughly 7 degrees)

I'm sorry, I'm still very confused about the TDC of the other pistons. I've read a number of threads, best was (2F Engine: *Valve Lash: Jim Chenoweth on Valve Adjustment.

This is what I understand; with the engine warm :

• The line represents TDC for piston 1. Distributor rotor should be lined up with the plug wire for cylinder 1. In this location, I should be able to check / adjust the intake / exhausts for 1-2-3-5-7-9.
• Rotate the camshaft 360 degrees. Valves for piston 1 should be down and valves for piston 6 should be up. Distributor rotor should also be lined with plug wire 6. Adjust the intake / exhausts for 4-6-8-10-11-12.

I pulled the valve cover off, yesterday just to get a feel of everything. I tried to measure the spacing for the valves and noticed valves 1 & 2 were at 0.010"; which is loose for the exhaust (0.014") and tight for the intake (0.008"). I was confused on why they were the same. Other valves were similar and could not slide the feeler gauge in. I adjusted the exhaust valve (#1) but then remembered the engine was cold and stopped.

What's the impact of having too tight / loose rocker arms? and as the engine warms up, would the gap increase; metal expands so it should get tighter?

I would appreciate your guidance / suggestions...i'm taking baby steps here

 

[Pighead]

• The line represents TDC for piston 1.

But also, at the very same time, represents TDC for piston 6. Hence the possibilities of confusing the TDCs and why we check more than one place to make sure.
What I might do, were I you, after you get underneath and clean off that part of your flywheel and paint it up pretty in a color of your choice, is to do a few dry runs adjusting your valves cold. Maybe 10 or 20 times. With all the covers off and sparkplugs out. Turn the crankshaft (not camshaft) by hand while watching the rotor and flywheel and rockers and pistons. There will be an "AHA!" moment.

 

[charliemeyer007]

I use white out, paint it on to the clean and surface, then blot it off carefully - it will stay on the perimeter of the BB and in the grove of the line - timing light reflects nicely. Mine is still there from 1982.

 

[sggoat]

I usually do my valves when changing plugs:

1. Motor hot - drain oil and pull the plugs​

2. Replace drain plug so you don’t make a mess.​

3. Remove valve cover, 4th gear and truck on a flat surface then rock the truck to TDC​

4. Adjust valves per FSM​

5. Rock 180 degrees to timing mark again​

6. Adjust remaining valves per FSM​

7. Replace valve cover, gap and install new plugs.​

8. Replace oil filter, refill with oil of your choice.​

9. Start and check/set timing​

10. Adjust idle and any other carb adjustment if required.​

​

Final step 7 = beer, your done​

think the engine needs 360 degrees to get it to #6 for the second batch of valve adj

 

[SergP]

So I found the line; its not very visible, but was half a turn further from the BB. (roughly 7 degrees)

I pulled the valve cover off, yesterday just to get a feel of everything. I tried to measure the spacing for the valves and noticed valves 1 & 2 were at 0.010"; which is loose for the exhaust (0.014") and tight for the intake (0.008"). I was confused on why they were the same. Other valves were similar and could not slide the feeler gauge in. I adjusted the exhaust valve (#1) but then remembered the engine was cold and stopped.

What's the impact of having too tight / loose rocker arms? and as the engine warms up, would the gap increase; metal expands so it should get tighter?

I would appreciate your guidance / suggestions...i'm taking baby steps here

Make sure when you find the line,,, your #1 piston is at the top... My first mistake..

 

[77mustard40]

think the engine needs 360 degrees to get it to #6 for the second batch of valve adj

Agreed, edited

 

[RevISK]

I usually do my valves when changing plugs:

1. Motor hot - drain oil and pull the plugs​

2. Replace drain plug so you don’t make a mess.​

3. Remove valve cover, 4th gear and truck on a flat surface then rock the truck to TDC​

4. Adjust valves per FSM​

5. Rock 180 360 degrees to timing mark again​

6. Adjust remaining valves per FSM​

7. Replace valve cover, gap and install new plugs.​

8. Replace oil filter, refill with oil of your choice.​

9. Start and check/set timing​

10. Adjust idle and any other carb adjustment if required.​

​

Final step 7 = beer, your done​

Hey Kelly,

Any chance you’d be into swinging by and supervising me through this sometime?
I’ve got everything I need to do this except I can’t find where I left my cajones.

Ian

 

[AYM707]

But also, at the very same time, represents TDC for piston 6. Hence the possibilities of confusing the TDCs and why we check more than one place to make sure.
What I might do, were I you, after you get underneath and clean off that part of your flywheel and paint it up pretty in a color of your choice, is to do a few dry runs adjusting your valves cold. Maybe 10 or 20 times. With all the covers off and sparkplugs out. Turn the crankshaft (not camshaft) by hand while watching the rotor and flywheel and rockers and pistons. There will be an "AHA!" moment.

@Pighead - you mean I have access to the fly wheel from below??? Will explore this weekend.

 

[Pighead]

@Pighead - you mean I have access to the fly wheel from below??? Will explore this weekend.

you don't absolutely HAVE to, it's just easier to find and clean and paint the marks. there's just a little sheet metal cover held on, usually, with just a couple slotted screws...

 

[AYM707]

you don't absolutely HAVE to, it's just easier to find and clean and paint the marks. there's just a little sheet metal cover held on, usually, with just a couple slotted screws...

That was a piece of cake. Painted...with white out (highly visible)

PO had used an assortment of bolts; now replaced. Notice there was remains of grey silicon gasket material ... but i dont think this is required.

Also over came my fear of opening the distributor (long story) and was able to confirm TDC for #6. Turned the engine until I was back on the line and the coil was pointing towards firing #1.

Even with the engine cold, there were some valves that were loose while others were tight.

Thank you @Pighead / @77mustard40 for getting me this far!