Hey guys. I recently replaced the passenger side cam tower on my SPFI 89 gl with a cam tower out of a carb EA82. I probably should've swapped my cam into the tower, but I didn't. I started the car the other day and it ran super rough. I thought maybe I timed it wrong, but its dead on. I did find a vacuum line that was disconnected. Tried to start it again tonight, and it doesn't even try to fire. My question is, are carb EA82 cams different than SPFI cams?

Not sure if it matters, but the only thing I left unhooked is the electric fan. I did that just in case I had to redo the timing. 

I'm going to check the distributor timing now, make sure it's still correct. The car ran when I parked it though so I dont see why that would be off. Who knows.

One way to check what you have physically is remove the rocker covers and look at .. I think it is the rings, by number, or their position along the cam itself. Compare left to right.

Hang, on, oddly enough, am sitting in a carpark and have my manual with me !! About the middle of the cam shaft are Identification Marks A and B. I think they shift about between different versions. Never tried mixing left to right , but you can't be the first. I run matched turbo cams in a non turbo. Not sure I can feel a difference. Early and late efi cams differed from each other. Carb differes from them

Distributor is on. #1 TDC, rotor at the brake booster, 20* on the crank.

I didn't swap cams from L to R, I put a whole passenger cam tower or housing from a carbureted EA82 with its cam into my SPFI EA82. Everything looks correct as far as timing belts, and distributor goes. And nothing is unhooked. Visually the 2 cams looked the same, but thats just visually. I still have the original cam, I just need to know if I need to swap my old cam in like I should've. 

yeah, i know what you did, they are not interchangeable left to right. So, visually, those two rings, machined looking rings are in same position on both sides? I don't have spfi specs

you swapped a tower from another engine, so rockers cant slip out on you, that has happened to me before. Compression test coming up?

Rocker arm fell off. Pull the valve cover and find out which one.

Double check timing, fuel, and vacuum.  

Are you positive you're not lining up all the marks at 12 oclock at the same time like modern EJ and other engines? 

Doubtful cam differences are enough for it not to run at all. 

I still bet it's the rocker arms but in the event it's looking confusing still , there's more to the story than "Well I spent the day swapping a cam for fun...".....what prompted the replacement?

The difference between the cams should not make it run rough. All you might notice is maybe a slight difference in power. I second idosubaru on double check the belt timing and the rocker arms. The cam I sold you I think was out of an '87 carbed.

One of the bolts holding the cam seals in was stripped out, and puking oil everywhere. I got lazy and tried to fix the hole while the cam tower was still in the car. I drilled it out, tapped it, and inserted a helicoil. When I went to put the cam seals back in it I realized I drilled the hole crooked. That's why I replaced the cam tower. I'll pull the valve cover tonight when I get home. 

On 10/22/2021 at 10:01 AM, Espey16 said:

One of the bolts holding the cam seals in was stripped out, and puking oil everywhere. I got lazy and tried to fix the hole while the cam tower was still in the car. I drilled it out, tapped it, and inserted a helicoil. When I went to put the cam seals back in it I realized I drilled the hole crooked. That's why I replaced the cam tower. I'll pull the valve cover tonight when I get home. 

If it happens again you can clean the hole with a tap and install a longer bolt to reach the lower threads that have never been used. 

I have heard of people installing the rocker arm without removing the tower. But they've never given much detail on how they did it.  I've tried it on an XT6 with no success, it's HLA's, rockers, pistons, valves are all the same as the EA82, so the localized process would be identical (same form factor around the rocker arm/hla).  But an EA82 is smaller and has more access/room and maybe yours will be a forward arm, mine were in the back with less room.  If you figure out away let me know, i've still got one i'd like to accomplish that with if you find an easy way!

I have the valve cover off now, and all 4 rockers are still on the lifters and valves.

Looking at the cams now, I'm pretty sure they're different. I didn't notice it before, but the SPFI cam has an A stamped in it right behind the seal, and an 11 stamped in it before the #3 lobes. The carb cam has the same A behind the seal, but a 10 before the #3 cam lobes.

Random question, is ultra gray the only recommended sealant for the cam tower? I have it off now, and it's all still tacky except what got squeezed out when I tightened the bolts down. I put the tower on 2 weeks ago, and waited 24 hours to try and start it.

Here are the 2 cams side by side. Carb up top, SPFI below.

I guess right and left.

Cams are swapped, tower is bolted back on, rocker arms are all in place. I'm not going to put the passenger belt back on till tomorrow, if not Wednesday if I get time to do it. I'll report back then.

interesting to see no grooves that the manuals indicate as ID marks, seen them myself and been relying on them in the future as I have a few cams from various lumped together. Have carb, early turbo, later turbo and later mpfi to try some day. Maybe no grooves were the first, so they look identical apart from the 10 and 11. If I can get at my collection I will look closer at what I have. Must be time to recoat in some oil anyway. Thanks for coming back.

 

Grey max, any fine goo usually does the job. I have seen red, blue and black as well. I like the grey, looks factory. Not set in two weeks is odd, but not had to pull too many apart after only two weeks. Once found my torque wrench was dodgy, so did a full tear down a day or two later, only to find it became dodgy after

Edited October 24, 20214 yr by Step-a-toe

Well, it wasn't the cam. Car still won't even try to fire. Thank you guys for all the input. Time to do some more searching.

The car is now running. I might have wasted everyone's time with this. While trying to start the car with each cam installed, the car was turning over like it was missing a timing belt if that makes sense. Just didn't sound right and didn't even try to fire. I just put little fuel in the tb and it started. Ran rough at first, but its idling fine now.

14 minutes ago, Espey16 said:

The car is now running. I might have wasted everyone's time with this. 

Great.  No waste, that's a successful effort getting the car running!  Feels good doesn't it?!