Safe to run engine without serpentine belt?

[Tyler]

Hey guys I’m Tyler and I’m new here on ETCG forums though I’ve been watching Eric the car guy on Youtube for awhile now.

I need to adjust the rockers on my 5.7l vortec engine with hydraulic roller lifters. I’ve read that the best way to do this is with the engine running.

The problem I have is this: To access the valve covers, the alternator and AC pump have to be removed. This means I also have to have the serpentine belt disconnected.

Is it safe to run the engine for the few minutes it takes to adjust the rockers with no water pump?

Thanks in advance,

Tyler

Topic

[Its me]

[quote=”masterelyt” post=87249]Hey guys I’m Tyler and I’m new here on ETCG forums though I’ve been watching Eric the car guy on Youtube for awhile now.

I need to adjust the rockers on my 5.7l vortec engine with hydraulic roller lifters. I’ve read that the best way to do this is with the engine running.

The problem I have is this: To access the valve covers, the alternator and AC pump have to be removed. This means I also have to have the serpentine belt disconnected.

Is it safe to run the engine for the few minutes it takes to adjust the rockers with no water pump?

Thanks in advance,

Tyler[/quote]

Did you mean to say in your last sentence “AC Pump”….

If so, yes, you can run it for very short periods and be OK…. Be aware though that some error codes may be set….

-Karl

[Tyler]

Thanks for the quick reply!

In my last sentence I actually meant water pump (in addition to AC pump and alternator and PS pump…) because they are all turned by the serpentine belt.

I figure if I’m quick enough and do it while the engine is cold, it won’t get too hot, what do you think?

[Its me]

OK, LOL… Lost in translation…. I translated “no water pump” as “water pump removed”…

Yes, it is OK for short periods, but don’t let it run more than a couple of minutes and keep an Eagle eye on the engine temperature……

And you may get some error codes, but just reset them…

-Karl

[Tyler]

Haha Thanks Karl!

I’ll give it a shot in the morning, not too concerned about error codes I just don’t want to damage anything. I’ll let you know how it goes once I’m done. 😛

[Tyler]

I got the rockers adjusted today, I ended up running the engine for a minute or two while I did one side then let it cool because it was getting hot way too fast. After awhile cooling I just did the same with the other side and then let it cool again before putting everything back together.

So it is possible but you are right, it’s necessary to keep a close eye on the temp because it rises faster than you’d think!

Thanks again,

Tyler

[EricTheCarGuy]

I’m glad you got that sorted out. Thanks for the update. If you don’t mind me asking, why were you adjusting the rockers? And did the adjustment accomplish what you had hoped?

[Tyler]

Hey Eric I was adjusting the rockers because I was investigating a noisy lifter on startup.

I took the push rods out so that I could try to concentrate some Seafoam down into the lifters to let them soak in an effort to clean out any debris that was blocking the offending lifter’s check valve.

Therefore I had to adjust the rocker arms when I put everything back together.

I actually adjusted them first with the engine off by running each rocker nut down until I could feel a slight drag while turning the push rod and then going 3/4 of a turn past that, but I ended up with quite a noisy valve train after that (noisier than when I began). So my second option was to adjust with the engine running.

To answer your question the adjustment helped to quiet the ticking lifter, but it’s still noticeable if you listen real carefully.

The engine does run smoother though at idle.

Thanks,

Tyler

[EricTheCarGuy]

I believe you have to rotate the engine to TDC on each cylinder before you do an adjustment like that. That said, if you decide to replace the lifters at some point, you’ll also need to replace the cam. You must replace cam and lifters as a set. You can’t replace just one or the other.

Thanks for the updates and the additional information.

[Tyler]

Hey Eric

According to my Haynes manual you can rotate to TDC #1 and do half the valves, then rotate to TDC #6 and do the others. That’s what I did.

Also I’ve read and heard from a few people that with the roller lifters, you can actually just change the lifters without changing the cam because the rollers don’t wear into a cam like flat lifters do. Have I been mislead?

[Author]

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